Re: [HACKERS] WAL logging problem in 9.4.3? - Mailing list pgsql-hackers
| From | Kyotaro Horiguchi |
|---|---|
| Subject | Re: [HACKERS] WAL logging problem in 9.4.3? |
| Date | |
| Msg-id | 20200121.184557.1462314355964996736.horikyota.ntt@gmail.com Whole thread Raw |
| In response to | Re: [HACKERS] WAL logging problem in 9.4.3? (Noah Misch <noah@leadboat.com>) |
| Responses |
Re: [HACKERS] WAL logging problem in 9.4.3?
(Noah Misch <noah@leadboat.com>)
|
| List | pgsql-hackers |
Thank you for the comment.
At Sat, 18 Jan 2020 19:51:39 -0800, Noah Misch <noah@leadboat.com> wrote in
> On Tue, Jan 14, 2020 at 07:35:22PM +0900, Kyotaro Horiguchi wrote:
> > At Thu, 26 Dec 2019 12:46:39 +0900 (JST), Kyotaro Horiguchi <horikyota.ntt@gmail.com> wrote in
> > > At Wed, 25 Dec 2019 16:15:21 -0800, Noah Misch <noah@leadboat.com> wrote in
> > > > === Defect 1: Forgets to skip WAL after SAVEPOINT; DROP TABLE; ROLLBACK TO
...
> > This is complex than expected. The DROP TABLE unconditionally removed
> > relcache entry. To fix that, I tried to use rd_isinvalid but it failed
> > because there's a state that a relcache invalid but the corresponding
> > catalog entry is alive.
> >
> > In the attached patch 0002, I added a boolean in relcache that
> > indicates that the relation is already removed in catalog but not
> > committed.
>
> This design could work, but some if its properties aren't ideal. For example,
> RelationIdGetRelation() can return a !rd_isvalid relation when the relation
> has been dropped. What others designs did you consider, if any?
I thought that the entries with rd_isdropped is true cannot be fetched
by other transactions because the relid is not seen there. Still the
same session could do that by repeatedly reindexing or invalidation on
the same relation and I think it is safe because the content of the
entry coudln't be changed and the cache content is reusable. That
being said, it is actually makes things unclear.
I came up with two alternatives. One is a variant of
RelationIdGetRelation for the purpose. The new function
RelationIdGetRelationCache is currently used (only) in ATExecAddIndex
so we could restrict it to return only dropped relations.
Another is another "stashed" relcache, but it seems to make things too
complex.
> On Thu, Jan 16, 2020 at 02:20:57PM +0900, Kyotaro Horiguchi wrote:
> > --- a/src/backend/utils/cache/relcache.c
> > +++ b/src/backend/utils/cache/relcache.c
> > @@ -3114,8 +3153,10 @@ AtEOXact_cleanup(Relation relation, bool isCommit)
> > */
> > if (relation->rd_createSubid != InvalidSubTransactionId)
> > {
> > - if (isCommit)
> > - relation->rd_createSubid = InvalidSubTransactionId;
> > + relation->rd_createSubid = InvalidSubTransactionId;
> > +
> > + if (isCommit && !relation->rd_isdropped)
> > + {} /* Nothing to do */
>
> What is the purpose of this particular change? This executes at the end of a
> top-level transaction. We've already done any necessary syncing, and we're
> clearing any flags that caused WAL skipping. I think it's no longer
> productive to treat dropped relations differently.
It executes the pending *relcache* drop we should have done in
ATPostAlterTypeCleanup (or in RelationClearRelation) if the newness
flags were false. The entry misses the chance of being removed (then
bloats the relcache) if we don't do that there. I added a comment
there to exlaining that.
> > @@ -3232,6 +3272,19 @@ AtEOSubXact_cleanup(Relation relation, bool isCommit,
> > }
> > }
> >
> > + /*
> > + * If this relation registered pending sync then dropped, subxact rollback
> > + * cancels the uncommitted drop, and commit propagates it to the parent.
> > + */
> > + if (relation->rd_isdropped)
> > + {
> > + Assert (!relation->rd_isvalid &&
> > + (relation->rd_createSubid != InvalidSubTransactionId ||
> > + relation->rd_firstRelfilenodeSubid != InvalidSubTransactionId));
> > + if (!isCommit)
> > + relation->rd_isdropped = false;
>
> This does the wrong thing when there exists some subtransaction rollback that
> does not rollback the DROP:
Sorry for my stupid. I actually thought something like that on the
way. After all, I concluded that the dropped flag ought to behave same
way with rd_createSubid.
> \pset null 'NULL'
> begin;
> create extension pg_visibility;
> create table droppedtest (c int);
> select 'droppedtest'::regclass::oid as oid \gset
> savepoint q; drop table droppedtest; release q; -- rd_dropped==true
> select * from pg_visibility_map(:oid); -- processes !rd_isvalid rel (not ideal)
> savepoint q; select 1; rollback to q; -- rd_dropped==false (wrong)
> savepoint q; select 1; rollback to q;
> select pg_relation_size(:oid), pg_relation_filepath(:oid),
> has_table_privilege(:oid, 'SELECT'); -- all nulls, okay
> select * from pg_visibility_map(:oid); -- assertion failure
> rollback;
And I teached RelationIdGetRelation not to return dropped
relations. So the (not ideal) cases just fail as before.
Three other fixes not mentined above are made. One is the useless
rd_firstRelfilenodeSubid in the condition to dicide whether to
preserve or not a relcache entry, and the forgotten copying of other
newness flags. Another is the forgotten SWAPFIELD on
rd_dropedSubid. The last is the forgotten change in
out/equal/copyfuncs.
Please find the attached.
regards.
--
Kyotaro Horiguchi
NTT Open Source Software Center
From 892ca76faec27a19f5bc17cd21af2a4dd827e56b Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Date: Thu, 21 Nov 2019 15:28:06 +0900
Subject: [PATCH v33 1/4] Rework WAL-skipping optimization
While wal_level=minimal we omit WAL-logging for certain some
operations on relfilenodes that are created in the current
transaction. The files are fsynced at commit. The machinery
accelerates bulk-insertion operations but it fails in certain sequence
of operations and a crash just after commit may leave broken table
files.
This patch overhauls the machinery so that WAL-loggings on all
operations are omitted for such relfilenodes. This patch also
introduces a new feature that small files are emitted as a WAL record
instead of syncing. The new GUC variable wal_skip_threshold controls
the threshold.
---
doc/src/sgml/config.sgml | 43 ++-
doc/src/sgml/perform.sgml | 47 +--
src/backend/access/common/toast_internals.c | 4 +-
src/backend/access/gist/gistutil.c | 31 +-
src/backend/access/gist/gistxlog.c | 21 ++
src/backend/access/heap/heapam.c | 45 +--
src/backend/access/heap/heapam_handler.c | 22 +-
src/backend/access/heap/rewriteheap.c | 21 +-
src/backend/access/nbtree/nbtsort.c | 41 +--
src/backend/access/rmgrdesc/gistdesc.c | 5 +
src/backend/access/transam/README | 45 ++-
src/backend/access/transam/xact.c | 15 +
src/backend/access/transam/xloginsert.c | 10 +-
src/backend/access/transam/xlogutils.c | 18 +-
src/backend/catalog/heap.c | 4 +
src/backend/catalog/storage.c | 248 ++++++++++++-
src/backend/commands/cluster.c | 12 +-
src/backend/commands/copy.c | 58 +--
src/backend/commands/createas.c | 11 +-
src/backend/commands/matview.c | 12 +-
src/backend/commands/tablecmds.c | 11 +-
src/backend/storage/buffer/bufmgr.c | 125 ++++++-
src/backend/storage/lmgr/lock.c | 12 +
src/backend/storage/smgr/md.c | 36 +-
src/backend/storage/smgr/smgr.c | 35 ++
src/backend/utils/cache/relcache.c | 159 +++++++--
src/backend/utils/misc/guc.c | 13 +
src/include/access/gist_private.h | 2 +
src/include/access/gistxlog.h | 1 +
src/include/access/heapam.h | 3 -
src/include/access/rewriteheap.h | 2 +-
src/include/access/tableam.h | 15 +-
src/include/catalog/storage.h | 6 +
src/include/storage/bufmgr.h | 4 +
src/include/storage/lock.h | 3 +
src/include/storage/smgr.h | 1 +
src/include/utils/rel.h | 57 ++-
src/include/utils/relcache.h | 8 +-
src/test/recovery/t/018_wal_optimize.pl | 374 ++++++++++++++++++++
src/test/regress/expected/alter_table.out | 6 +
src/test/regress/sql/alter_table.sql | 7 +
41 files changed, 1242 insertions(+), 351 deletions(-)
create mode 100644 src/test/recovery/t/018_wal_optimize.pl
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 3ccacd528b..cd5c065de3 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -2481,21 +2481,14 @@ include_dir 'conf.d'
levels. This parameter can only be set at server start.
</para>
<para>
- In <literal>minimal</literal> level, WAL-logging of some bulk
- operations can be safely skipped, which can make those
- operations much faster (see <xref linkend="populate-pitr"/>).
- Operations in which this optimization can be applied include:
- <simplelist>
- <member><command>CREATE TABLE AS</command></member>
- <member><command>CREATE INDEX</command></member>
- <member><command>CLUSTER</command></member>
- <member><command>COPY</command> into tables that were created or truncated in the same
- transaction</member>
- </simplelist>
- But minimal WAL does not contain enough information to reconstruct the
- data from a base backup and the WAL logs, so <literal>replica</literal> or
- higher must be used to enable WAL archiving
- (<xref linkend="guc-archive-mode"/>) and streaming replication.
+ In <literal>minimal</literal> level, no information is logged for
+ tables or indexes for the remainder of a transaction that creates or
+ truncates them. This can make bulk operations much faster (see
+ <xref linkend="populate-pitr"/>). But minimal WAL does not contain
+ enough information to reconstruct the data from a base backup and the
+ WAL logs, so <literal>replica</literal> or higher must be used to
+ enable WAL archiving (<xref linkend="guc-archive-mode"/>) and
+ streaming replication.
</para>
<para>
In <literal>logical</literal> level, the same information is logged as
@@ -2887,6 +2880,26 @@ include_dir 'conf.d'
</listitem>
</varlistentry>
+ <varlistentry id="guc-wal-skip-threshold" xreflabel="wal_skip_threshold">
+ <term><varname>wal_skip_threshold</varname> (<type>integer</type>)
+ <indexterm>
+ <primary><varname>wal_skip_threshold</varname> configuration parameter</primary>
+ </indexterm>
+ </term>
+ <listitem>
+ <para>
+ When <varname>wal_level</varname> is <literal>minimal</literal> and a
+ transaction commits after creating or rewriting a permanent table,
+ materialized view, or index, this setting determines how to persist
+ the new data. If the data is smaller than this setting, write it to
+ the WAL log; otherwise, use an fsync of the data file. Depending on
+ the properties of your storage, raising or lowering this value might
+ help if such commits are slowing concurrent transactions. The default
+ is two megabytes (<literal>2MB</literal>).
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry id="guc-commit-delay" xreflabel="commit_delay">
<term><varname>commit_delay</varname> (<type>integer</type>)
<indexterm>
diff --git a/doc/src/sgml/perform.sgml b/doc/src/sgml/perform.sgml
index 0f61b0995d..12fda690fa 100644
--- a/doc/src/sgml/perform.sgml
+++ b/doc/src/sgml/perform.sgml
@@ -1606,8 +1606,8 @@ SELECT * FROM x, y, a, b, c WHERE something AND somethingelse;
needs to be written, because in case of an error, the files
containing the newly loaded data will be removed anyway.
However, this consideration only applies when
- <xref linkend="guc-wal-level"/> is <literal>minimal</literal> for
- non-partitioned tables as all commands must write WAL otherwise.
+ <xref linkend="guc-wal-level"/> is <literal>minimal</literal>
+ as all commands must write WAL otherwise.
</para>
</sect2>
@@ -1707,42 +1707,13 @@ SELECT * FROM x, y, a, b, c WHERE something AND somethingelse;
</para>
<para>
- Aside from avoiding the time for the archiver or WAL sender to
- process the WAL data,
- doing this will actually make certain commands faster, because they
- are designed not to write WAL at all if <varname>wal_level</varname>
- is <literal>minimal</literal>. (They can guarantee crash safety more cheaply
- by doing an <function>fsync</function> at the end than by writing WAL.)
- This applies to the following commands:
- <itemizedlist>
- <listitem>
- <para>
- <command>CREATE TABLE AS SELECT</command>
- </para>
- </listitem>
- <listitem>
- <para>
- <command>CREATE INDEX</command> (and variants such as
- <command>ALTER TABLE ADD PRIMARY KEY</command>)
- </para>
- </listitem>
- <listitem>
- <para>
- <command>ALTER TABLE SET TABLESPACE</command>
- </para>
- </listitem>
- <listitem>
- <para>
- <command>CLUSTER</command>
- </para>
- </listitem>
- <listitem>
- <para>
- <command>COPY FROM</command>, when the target table has been
- created or truncated earlier in the same transaction
- </para>
- </listitem>
- </itemizedlist>
+ Aside from avoiding the time for the archiver or WAL sender to process the
+ WAL data, doing this will actually make certain commands faster, because
+ they do not to write WAL at all if <varname>wal_level</varname>
+ is <literal>minimal</literal> and the current subtransaction (or top-level
+ transaction) created or truncated the table or index they change. (They
+ can guarantee crash safety more cheaply by doing
+ an <function>fsync</function> at the end than by writing WAL.)
</para>
</sect2>
diff --git a/src/backend/access/common/toast_internals.c b/src/backend/access/common/toast_internals.c
index 65801a2a84..25a81e5ec6 100644
--- a/src/backend/access/common/toast_internals.c
+++ b/src/backend/access/common/toast_internals.c
@@ -528,8 +528,8 @@ toast_get_valid_index(Oid toastoid, LOCKMODE lock)
validIndexOid = RelationGetRelid(toastidxs[validIndex]);
/* Close the toast relation and all its indexes */
- toast_close_indexes(toastidxs, num_indexes, lock);
- table_close(toastrel, lock);
+ toast_close_indexes(toastidxs, num_indexes, NoLock);
+ table_close(toastrel, NoLock);
return validIndexOid;
}
diff --git a/src/backend/access/gist/gistutil.c b/src/backend/access/gist/gistutil.c
index dd975b164c..765329bbcd 100644
--- a/src/backend/access/gist/gistutil.c
+++ b/src/backend/access/gist/gistutil.c
@@ -1004,23 +1004,44 @@ gistproperty(Oid index_oid, int attno,
}
/*
- * Temporary and unlogged GiST indexes are not WAL-logged, but we need LSNs
- * to detect concurrent page splits anyway. This function provides a fake
- * sequence of LSNs for that purpose.
+ * Some indexes are not WAL-logged, but we need LSNs to detect concurrent page
+ * splits anyway. This function provides a fake sequence of LSNs for that
+ * purpose.
*/
XLogRecPtr
gistGetFakeLSN(Relation rel)
{
- static XLogRecPtr counter = FirstNormalUnloggedLSN;
-
if (rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP)
{
/*
* Temporary relations are only accessible in our session, so a simple
* backend-local counter will do.
*/
+ static XLogRecPtr counter = FirstNormalUnloggedLSN;
+
return counter++;
}
+ else if (rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+ {
+ /*
+ * WAL-logging on this relation will start after commit, so its LSNs
+ * must be distinct numbers smaller than the LSN at the next commit.
+ * Emit a dummy WAL record if insert-LSN hasn't advanced after the
+ * last call.
+ */
+ static XLogRecPtr lastlsn = InvalidXLogRecPtr;
+ XLogRecPtr currlsn = GetXLogInsertRecPtr();
+
+ /* Shouldn't be called for WAL-logging relations */
+ Assert(!RelationNeedsWAL(rel));
+
+ /* No need for an actual record if we already have a distinct LSN */
+ if (!XLogRecPtrIsInvalid(lastlsn) && lastlsn == currlsn)
+ currlsn = gistXLogAssignLSN();
+
+ lastlsn = currlsn;
+ return currlsn;
+ }
else
{
/*
diff --git a/src/backend/access/gist/gistxlog.c b/src/backend/access/gist/gistxlog.c
index d3f3a7b803..b60dba052f 100644
--- a/src/backend/access/gist/gistxlog.c
+++ b/src/backend/access/gist/gistxlog.c
@@ -449,6 +449,9 @@ gist_redo(XLogReaderState *record)
case XLOG_GIST_PAGE_DELETE:
gistRedoPageDelete(record);
break;
+ case XLOG_GIST_ASSIGN_LSN:
+ /* nop. See gistGetFakeLSN(). */
+ break;
default:
elog(PANIC, "gist_redo: unknown op code %u", info);
}
@@ -592,6 +595,24 @@ gistXLogPageDelete(Buffer buffer, FullTransactionId xid,
return recptr;
}
+/*
+ * Write an empty XLOG record to assign a distinct LSN.
+ */
+XLogRecPtr
+gistXLogAssignLSN(void)
+{
+ int dummy = 0;
+
+ /*
+ * Records other than SWITCH_WAL must have content. We use an integer 0 to
+ * follow the restriction.
+ */
+ XLogBeginInsert();
+ XLogSetRecordFlags(XLOG_MARK_UNIMPORTANT);
+ XLogRegisterData((char *) &dummy, sizeof(dummy));
+ return XLogInsert(RM_GIST_ID, XLOG_GIST_ASSIGN_LSN);
+}
+
/*
* Write XLOG record about reuse of a deleted page.
*/
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 5ddb6e85e9..92d9da23f7 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -21,7 +21,6 @@
* heap_multi_insert - insert multiple tuples into a relation
* heap_delete - delete a tuple from a relation
* heap_update - replace a tuple in a relation with another tuple
- * heap_sync - sync heap, for when no WAL has been written
*
* NOTES
* This file contains the heap_ routines which implement
@@ -1936,7 +1935,7 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
MarkBufferDirty(buffer);
/* XLOG stuff */
- if (!(options & HEAP_INSERT_SKIP_WAL) && RelationNeedsWAL(relation))
+ if (RelationNeedsWAL(relation))
{
xl_heap_insert xlrec;
xl_heap_header xlhdr;
@@ -2119,7 +2118,7 @@ heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
/* currently not needed (thus unsupported) for heap_multi_insert() */
AssertArg(!(options & HEAP_INSERT_NO_LOGICAL));
- needwal = !(options & HEAP_INSERT_SKIP_WAL) && RelationNeedsWAL(relation);
+ needwal = RelationNeedsWAL(relation);
saveFreeSpace = RelationGetTargetPageFreeSpace(relation,
HEAP_DEFAULT_FILLFACTOR);
@@ -8920,46 +8919,6 @@ heap2_redo(XLogReaderState *record)
}
}
-/*
- * heap_sync - sync a heap, for use when no WAL has been written
- *
- * This forces the heap contents (including TOAST heap if any) down to disk.
- * If we skipped using WAL, and WAL is otherwise needed, we must force the
- * relation down to disk before it's safe to commit the transaction. This
- * requires writing out any dirty buffers and then doing a forced fsync.
- *
- * Indexes are not touched. (Currently, index operations associated with
- * the commands that use this are WAL-logged and so do not need fsync.
- * That behavior might change someday, but in any case it's likely that
- * any fsync decisions required would be per-index and hence not appropriate
- * to be done here.)
- */
-void
-heap_sync(Relation rel)
-{
- /* non-WAL-logged tables never need fsync */
- if (!RelationNeedsWAL(rel))
- return;
-
- /* main heap */
- FlushRelationBuffers(rel);
- /* FlushRelationBuffers will have opened rd_smgr */
- smgrimmedsync(rel->rd_smgr, MAIN_FORKNUM);
-
- /* FSM is not critical, don't bother syncing it */
-
- /* toast heap, if any */
- if (OidIsValid(rel->rd_rel->reltoastrelid))
- {
- Relation toastrel;
-
- toastrel = table_open(rel->rd_rel->reltoastrelid, AccessShareLock);
- FlushRelationBuffers(toastrel);
- smgrimmedsync(toastrel->rd_smgr, MAIN_FORKNUM);
- table_close(toastrel, AccessShareLock);
- }
-}
-
/*
* Mask a heap page before performing consistency checks on it.
*/
diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c
index 1f6f6d0ea9..14f939d6b1 100644
--- a/src/backend/access/heap/heapam_handler.c
+++ b/src/backend/access/heap/heapam_handler.c
@@ -555,17 +555,6 @@ tuple_lock_retry:
return result;
}
-static void
-heapam_finish_bulk_insert(Relation relation, int options)
-{
- /*
- * If we skipped writing WAL, then we need to sync the heap (but not
- * indexes since those use WAL anyway / don't go through tableam)
- */
- if (options & HEAP_INSERT_SKIP_WAL)
- heap_sync(relation);
-}
-
/* ------------------------------------------------------------------------
* DDL related callbacks for heap AM.
@@ -698,7 +687,6 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
IndexScanDesc indexScan;
TableScanDesc tableScan;
HeapScanDesc heapScan;
- bool use_wal;
bool is_system_catalog;
Tuplesortstate *tuplesort;
TupleDesc oldTupDesc = RelationGetDescr(OldHeap);
@@ -713,12 +701,9 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
is_system_catalog = IsSystemRelation(OldHeap);
/*
- * We need to log the copied data in WAL iff WAL archiving/streaming is
- * enabled AND it's a WAL-logged rel.
+ * Valid smgr_targblock implies something already wrote to the relation.
+ * This may be harmless, but this function hasn't planned for it.
*/
- use_wal = XLogIsNeeded() && RelationNeedsWAL(NewHeap);
-
- /* use_wal off requires smgr_targblock be initially invalid */
Assert(RelationGetTargetBlock(NewHeap) == InvalidBlockNumber);
/* Preallocate values/isnull arrays */
@@ -728,7 +713,7 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
/* Initialize the rewrite operation */
rwstate = begin_heap_rewrite(OldHeap, NewHeap, OldestXmin, *xid_cutoff,
- *multi_cutoff, use_wal);
+ *multi_cutoff);
/* Set up sorting if wanted */
@@ -2524,7 +2509,6 @@ static const TableAmRoutine heapam_methods = {
.tuple_delete = heapam_tuple_delete,
.tuple_update = heapam_tuple_update,
.tuple_lock = heapam_tuple_lock,
- .finish_bulk_insert = heapam_finish_bulk_insert,
.tuple_fetch_row_version = heapam_fetch_row_version,
.tuple_get_latest_tid = heap_get_latest_tid,
diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index 5869922ff8..ba4dab2ba6 100644
--- a/src/backend/access/heap/rewriteheap.c
+++ b/src/backend/access/heap/rewriteheap.c
@@ -136,7 +136,6 @@ typedef struct RewriteStateData
Page rs_buffer; /* page currently being built */
BlockNumber rs_blockno; /* block where page will go */
bool rs_buffer_valid; /* T if any tuples in buffer */
- bool rs_use_wal; /* must we WAL-log inserts? */
bool rs_logical_rewrite; /* do we need to do logical rewriting */
TransactionId rs_oldest_xmin; /* oldest xmin used by caller to determine
* tuple visibility */
@@ -230,15 +229,13 @@ static void logical_end_heap_rewrite(RewriteState state);
* oldest_xmin xid used by the caller to determine which tuples are dead
* freeze_xid xid before which tuples will be frozen
* cutoff_multi multixact before which multis will be removed
- * use_wal should the inserts to the new heap be WAL-logged?
*
* Returns an opaque RewriteState, allocated in current memory context,
* to be used in subsequent calls to the other functions.
*/
RewriteState
begin_heap_rewrite(Relation old_heap, Relation new_heap, TransactionId oldest_xmin,
- TransactionId freeze_xid, MultiXactId cutoff_multi,
- bool use_wal)
+ TransactionId freeze_xid, MultiXactId cutoff_multi)
{
RewriteState state;
MemoryContext rw_cxt;
@@ -263,7 +260,6 @@ begin_heap_rewrite(Relation old_heap, Relation new_heap, TransactionId oldest_xm
/* new_heap needn't be empty, just locked */
state->rs_blockno = RelationGetNumberOfBlocks(new_heap);
state->rs_buffer_valid = false;
- state->rs_use_wal = use_wal;
state->rs_oldest_xmin = oldest_xmin;
state->rs_freeze_xid = freeze_xid;
state->rs_cutoff_multi = cutoff_multi;
@@ -322,7 +318,7 @@ end_heap_rewrite(RewriteState state)
/* Write the last page, if any */
if (state->rs_buffer_valid)
{
- if (state->rs_use_wal)
+ if (RelationNeedsWAL(state->rs_new_rel))
log_newpage(&state->rs_new_rel->rd_node,
MAIN_FORKNUM,
state->rs_blockno,
@@ -337,18 +333,14 @@ end_heap_rewrite(RewriteState state)
}
/*
- * If the rel is WAL-logged, must fsync before commit. We use heap_sync
- * to ensure that the toast table gets fsync'd too.
- *
- * It's obvious that we must do this when not WAL-logging. It's less
- * obvious that we have to do it even if we did WAL-log the pages. The
+ * When we WAL-logged rel pages, we must nonetheless fsync them. The
* reason is the same as in storage.c's RelationCopyStorage(): we're
* writing data that's not in shared buffers, and so a CHECKPOINT
* occurring during the rewriteheap operation won't have fsync'd data we
* wrote before the checkpoint.
*/
if (RelationNeedsWAL(state->rs_new_rel))
- heap_sync(state->rs_new_rel);
+ smgrimmedsync(state->rs_new_rel->rd_smgr, MAIN_FORKNUM);
logical_end_heap_rewrite(state);
@@ -646,9 +638,6 @@ raw_heap_insert(RewriteState state, HeapTuple tup)
{
int options = HEAP_INSERT_SKIP_FSM;
- if (!state->rs_use_wal)
- options |= HEAP_INSERT_SKIP_WAL;
-
/*
* While rewriting the heap for VACUUM FULL / CLUSTER, make sure data
* for the TOAST table are not logically decoded. The main heap is
@@ -687,7 +676,7 @@ raw_heap_insert(RewriteState state, HeapTuple tup)
/* Doesn't fit, so write out the existing page */
/* XLOG stuff */
- if (state->rs_use_wal)
+ if (RelationNeedsWAL(state->rs_new_rel))
log_newpage(&state->rs_new_rel->rd_node,
MAIN_FORKNUM,
state->rs_blockno,
diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c
index f163491d60..77f03ad4fe 100644
--- a/src/backend/access/nbtree/nbtsort.c
+++ b/src/backend/access/nbtree/nbtsort.c
@@ -31,18 +31,6 @@
* them. They will need to be re-read into shared buffers on first use after
* the build finishes.
*
- * Since the index will never be used unless it is completely built,
- * from a crash-recovery point of view there is no need to WAL-log the
- * steps of the build. After completing the index build, we can just sync
- * the whole file to disk using smgrimmedsync() before exiting this module.
- * This can be seen to be sufficient for crash recovery by considering that
- * it's effectively equivalent to what would happen if a CHECKPOINT occurred
- * just after the index build. However, it is clearly not sufficient if the
- * DBA is using the WAL log for PITR or replication purposes, since another
- * machine would not be able to reconstruct the index from WAL. Therefore,
- * we log the completed index pages to WAL if and only if WAL archiving is
- * active.
- *
* This code isn't concerned about the FSM at all. The caller is responsible
* for initializing that.
*
@@ -563,12 +551,7 @@ _bt_leafbuild(BTSpool *btspool, BTSpool *btspool2)
wstate.heap = btspool->heap;
wstate.index = btspool->index;
wstate.inskey = _bt_mkscankey(wstate.index, NULL);
-
- /*
- * We need to log index creation in WAL iff WAL archiving/streaming is
- * enabled UNLESS the index isn't WAL-logged anyway.
- */
- wstate.btws_use_wal = XLogIsNeeded() && RelationNeedsWAL(wstate.index);
+ wstate.btws_use_wal = RelationNeedsWAL(wstate.index);
/* reserve the metapage */
wstate.btws_pages_alloced = BTREE_METAPAGE + 1;
@@ -1265,21 +1248,15 @@ _bt_load(BTWriteState *wstate, BTSpool *btspool, BTSpool *btspool2)
_bt_uppershutdown(wstate, state);
/*
- * If the index is WAL-logged, we must fsync it down to disk before it's
- * safe to commit the transaction. (For a non-WAL-logged index we don't
- * care since the index will be uninteresting after a crash anyway.)
- *
- * It's obvious that we must do this when not WAL-logging the build. It's
- * less obvious that we have to do it even if we did WAL-log the index
- * pages. The reason is that since we're building outside shared buffers,
- * a CHECKPOINT occurring during the build has no way to flush the
- * previously written data to disk (indeed it won't know the index even
- * exists). A crash later on would replay WAL from the checkpoint,
- * therefore it wouldn't replay our earlier WAL entries. If we do not
- * fsync those pages here, they might still not be on disk when the crash
- * occurs.
+ * When we WAL-logged index pages, we must nonetheless fsync index files.
+ * Since we're building outside shared buffers, a CHECKPOINT occurring
+ * during the build has no way to flush the previously written data to
+ * disk (indeed it won't know the index even exists). A crash later on
+ * would replay WAL from the checkpoint, therefore it wouldn't replay our
+ * earlier WAL entries. If we do not fsync those pages here, they might
+ * still not be on disk when the crash occurs.
*/
- if (RelationNeedsWAL(wstate->index))
+ if (wstate->btws_use_wal)
{
RelationOpenSmgr(wstate->index);
smgrimmedsync(wstate->index->rd_smgr, MAIN_FORKNUM);
diff --git a/src/backend/access/rmgrdesc/gistdesc.c b/src/backend/access/rmgrdesc/gistdesc.c
index 3377367e12..cfcc8885ea 100644
--- a/src/backend/access/rmgrdesc/gistdesc.c
+++ b/src/backend/access/rmgrdesc/gistdesc.c
@@ -80,6 +80,9 @@ gist_desc(StringInfo buf, XLogReaderState *record)
case XLOG_GIST_PAGE_DELETE:
out_gistxlogPageDelete(buf, (gistxlogPageDelete *) rec);
break;
+ case XLOG_GIST_ASSIGN_LSN:
+ /* No details to write out */
+ break;
}
}
@@ -104,6 +107,8 @@ gist_identify(uint8 info)
break;
case XLOG_GIST_PAGE_DELETE:
id = "PAGE_DELETE";
+ case XLOG_GIST_ASSIGN_LSN:
+ id = "ASSIGN_LSN";
break;
}
diff --git a/src/backend/access/transam/README b/src/backend/access/transam/README
index b5a2cb2de8..eb9aac5fd3 100644
--- a/src/backend/access/transam/README
+++ b/src/backend/access/transam/README
@@ -717,6 +717,38 @@ then restart recovery. This is part of the reason for not writing a WAL
entry until we've successfully done the original action.
+Skipping WAL for New RelFileNode
+--------------------------------
+
+Under wal_level=minimal, if a change modifies a relfilenode that ROLLBACK
+would unlink, in-tree access methods write no WAL for that change. Code that
+writes WAL without calling RelationNeedsWAL() must check for this case. This
+skipping is mandatory. If a WAL-writing change preceded a WAL-skipping change
+for the same block, REDO could overwrite the WAL-skipping change. If a
+WAL-writing change followed a WAL-skipping change for the same block, a
+related problem would arise. When a WAL record contains no full-page image,
+REDO expects the page to match its contents from just before record insertion.
+A WAL-skipping change may not reach disk at all, violating REDO's expectation
+under full_page_writes=off. For any access method, CommitTransaction() writes
+and fsyncs affected blocks before recording the commit.
+
+Prefer to do the same in future access methods. However, two other approaches
+can work. First, an access method can irreversibly transition a given fork
+from WAL-skipping to WAL-writing by calling FlushRelationBuffers() and
+smgrimmedsync(). Second, an access method can opt to write WAL
+unconditionally for permanent relations. Under these approaches, the access
+method callbacks must not call functions that react to RelationNeedsWAL().
+
+This applies only to WAL records whose replay would modify bytes stored in the
+new relfilenode. It does not apply to other records about the relfilenode,
+such as XLOG_SMGR_CREATE. Because it operates at the level of individual
+relfilenodes, RelationNeedsWAL() can differ for tightly-coupled relations.
+Consider "CREATE TABLE t (); BEGIN; ALTER TABLE t ADD c text; ..." in which
+ALTER TABLE adds a TOAST relation. The TOAST relation will skip WAL, while
+the table owning it will not. ALTER TABLE SET TABLESPACE will cause a table
+to skip WAL, but that won't affect its indexes.
+
+
Asynchronous Commit
-------------------
@@ -820,13 +852,12 @@ Changes to a temp table are not WAL-logged, hence could reach disk in
advance of T1's commit, but we don't care since temp table contents don't
survive crashes anyway.
-Database writes made via any of the paths we have introduced to avoid WAL
-overhead for bulk updates are also safe. In these cases it's entirely
-possible for the data to reach disk before T1's commit, because T1 will
-fsync it down to disk without any sort of interlock, as soon as it finishes
-the bulk update. However, all these paths are designed to write data that
-no other transaction can see until after T1 commits. The situation is thus
-not different from ordinary WAL-logged updates.
+Database writes that skip WAL for new relfilenodes are also safe. In these
+cases it's entirely possible for the data to reach disk before T1's commit,
+because T1 will fsync it down to disk without any sort of interlock. However,
+all these paths are designed to write data that no other transaction can see
+until after T1 commits. The situation is thus not different from ordinary
+WAL-logged updates.
Transaction Emulation during Recovery
-------------------------------------
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 017f03b6d8..118f9d521c 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -2109,6 +2109,13 @@ CommitTransaction(void)
*/
PreCommit_on_commit_actions();
+ /*
+ * Synchronize files that are created and not WAL-logged during this
+ * transaction. This must happen before AtEOXact_RelationMap(), so that we
+ * don't see committed-but-broken files after a crash.
+ */
+ smgrDoPendingSyncs(true);
+
/* close large objects before lower-level cleanup */
AtEOXact_LargeObject(true);
@@ -2342,6 +2349,13 @@ PrepareTransaction(void)
*/
PreCommit_on_commit_actions();
+ /*
+ * Synchronize files that are created and not WAL-logged during this
+ * transaction. This must happen before EndPrepare(), so that we don't see
+ * committed-but-broken files after a crash and COMMIT PREPARED.
+ */
+ smgrDoPendingSyncs(true);
+
/* close large objects before lower-level cleanup */
AtEOXact_LargeObject(true);
@@ -2660,6 +2674,7 @@ AbortTransaction(void)
*/
AfterTriggerEndXact(false); /* 'false' means it's abort */
AtAbort_Portals();
+ smgrDoPendingSyncs(false);
AtEOXact_LargeObject(false);
AtAbort_Notify();
AtEOXact_RelationMap(false, is_parallel_worker);
diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c
index 2fa0a7f667..a618dec776 100644
--- a/src/backend/access/transam/xloginsert.c
+++ b/src/backend/access/transam/xloginsert.c
@@ -1043,8 +1043,13 @@ log_newpage_range(Relation rel, ForkNumber forkNum,
BlockNumber startblk, BlockNumber endblk,
bool page_std)
{
+ int flags;
BlockNumber blkno;
+ flags = REGBUF_FORCE_IMAGE;
+ if (page_std)
+ flags |= REGBUF_STANDARD;
+
/*
* Iterate over all the pages in the range. They are collected into
* batches of XLR_MAX_BLOCK_ID pages, and a single WAL-record is written
@@ -1066,7 +1071,8 @@ log_newpage_range(Relation rel, ForkNumber forkNum,
nbufs = 0;
while (nbufs < XLR_MAX_BLOCK_ID && blkno < endblk)
{
- Buffer buf = ReadBuffer(rel, blkno);
+ Buffer buf = ReadBufferExtended(rel, forkNum, blkno,
+ RBM_NORMAL, NULL);
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
@@ -1088,7 +1094,7 @@ log_newpage_range(Relation rel, ForkNumber forkNum,
START_CRIT_SECTION();
for (i = 0; i < nbufs; i++)
{
- XLogRegisterBuffer(i, bufpack[i], REGBUF_FORCE_IMAGE | REGBUF_STANDARD);
+ XLogRegisterBuffer(i, bufpack[i], flags);
MarkBufferDirty(bufpack[i]);
}
diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c
index b55c383370..2bbce46041 100644
--- a/src/backend/access/transam/xlogutils.c
+++ b/src/backend/access/transam/xlogutils.c
@@ -544,6 +544,8 @@ typedef FakeRelCacheEntryData *FakeRelCacheEntry;
* fields related to physical storage, like rd_rel, are initialized, so the
* fake entry is only usable in low-level operations like ReadBuffer().
*
+ * This is also used for syncing WAL-skipped files.
+ *
* Caller must free the returned entry with FreeFakeRelcacheEntry().
*/
Relation
@@ -552,18 +554,20 @@ CreateFakeRelcacheEntry(RelFileNode rnode)
FakeRelCacheEntry fakeentry;
Relation rel;
- Assert(InRecovery);
-
/* Allocate the Relation struct and all related space in one block. */
fakeentry = palloc0(sizeof(FakeRelCacheEntryData));
rel = (Relation) fakeentry;
rel->rd_rel = &fakeentry->pgc;
rel->rd_node = rnode;
- /* We will never be working with temp rels during recovery */
+
+ /*
+ * We will never be working with temp rels during recovery or while
+ * syncing WAL-skipped files.
+ */
rel->rd_backend = InvalidBackendId;
- /* It must be a permanent table if we're in recovery. */
+ /* It must be a permanent table here */
rel->rd_rel->relpersistence = RELPERSISTENCE_PERMANENT;
/* We don't know the name of the relation; use relfilenode instead */
@@ -572,9 +576,9 @@ CreateFakeRelcacheEntry(RelFileNode rnode)
/*
* We set up the lockRelId in case anything tries to lock the dummy
* relation. Note that this is fairly bogus since relNode may be
- * different from the relation's OID. It shouldn't really matter though,
- * since we are presumably running by ourselves and can't have any lock
- * conflicts ...
+ * different from the relation's OID. It shouldn't really matter though.
+ * In recovery, we are running by ourselves and can't have any lock
+ * conflicts. While syncing, we already hold AccessExclusiveLock.
*/
rel->rd_lockInfo.lockRelId.dbId = rnode.dbNode;
rel->rd_lockInfo.lockRelId.relId = rnode.relNode;
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 0fdff2918f..9f58ef1378 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -439,6 +439,10 @@ heap_create(const char *relname,
break;
}
}
+ else
+ {
+ rel->rd_createSubid = InvalidSubTransactionId;
+ }
return rel;
}
diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c
index fddfbf1d8c..8253c420ef 100644
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@@ -29,9 +29,13 @@
#include "miscadmin.h"
#include "storage/freespace.h"
#include "storage/smgr.h"
+#include "utils/hsearch.h"
#include "utils/memutils.h"
#include "utils/rel.h"
+/* GUC variables */
+int wal_skip_threshold = 2048; /* in kilobytes */
+
/*
* We keep a list of all relations (represented as RelFileNode values)
* that have been created or deleted in the current transaction. When
@@ -61,7 +65,14 @@ typedef struct PendingRelDelete
struct PendingRelDelete *next; /* linked-list link */
} PendingRelDelete;
+typedef struct pendingSync
+{
+ RelFileNode rnode;
+ BlockNumber max_truncated;
+} pendingSync;
+
static PendingRelDelete *pendingDeletes = NULL; /* head of linked list */
+HTAB *pendingSyncHash = NULL;
/*
* RelationCreateStorage
@@ -117,6 +128,35 @@ RelationCreateStorage(RelFileNode rnode, char relpersistence)
pending->next = pendingDeletes;
pendingDeletes = pending;
+ /*
+ * If the relation needs at-commit sync, we also need to track the maximum
+ * unsynced truncated block; see smgrDoPendingSyncs().
+ */
+ if (relpersistence == RELPERSISTENCE_PERMANENT && !XLogIsNeeded())
+ {
+ pendingSync *pending;
+ bool found;
+
+ /* we sync only permanent relations */
+ Assert(backend == InvalidBackendId);
+
+ if (!pendingSyncHash)
+ {
+ HASHCTL ctl;
+
+ ctl.keysize = sizeof(RelFileNode);
+ ctl.entrysize = sizeof(pendingSync);
+ ctl.hcxt = TopTransactionContext;
+ pendingSyncHash =
+ hash_create("max truncated block hash",
+ 16, &ctl, HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
+ }
+
+ pending = hash_search(pendingSyncHash, &rnode, HASH_ENTER, &found);
+ Assert(!found);
+ pending->max_truncated = 0;
+ }
+
return srel;
}
@@ -216,6 +256,8 @@ RelationPreserveStorage(RelFileNode rnode, bool atCommit)
prev = pending;
}
}
+
+ /* FIXME what to do about pending syncs? */
}
/*
@@ -275,6 +317,8 @@ RelationTruncate(Relation rel, BlockNumber nblocks)
}
}
+ RelationPreTruncate(rel);
+
/*
* We WAL-log the truncation before actually truncating, which means
* trouble if the truncation fails. If we then crash, the WAL replay
@@ -325,6 +369,34 @@ RelationTruncate(Relation rel, BlockNumber nblocks)
FreeSpaceMapVacuumRange(rel, nblocks, InvalidBlockNumber);
}
+/*
+ * RelationPreTruncate
+ * Perform AM-independent work before a physical truncation.
+ *
+ * If an access method's relation_nontransactional_truncate does not call
+ * RelationTruncate(), it must call this before decreasing the table size.
+ */
+void
+RelationPreTruncate(Relation rel)
+{
+ pendingSync *pending;
+
+ if (!pendingSyncHash)
+ return;
+ RelationOpenSmgr(rel);
+
+ /* Record largest maybe-unsynced block of files under tracking */
+ pending = hash_search(pendingSyncHash, &(rel->rd_smgr->smgr_rnode.node),
+ HASH_FIND, NULL);
+ if (pending)
+ {
+ BlockNumber nblocks = smgrnblocks(rel->rd_smgr, MAIN_FORKNUM);
+
+ if (pending->max_truncated < nblocks)
+ pending->max_truncated = nblocks;
+ }
+}
+
/*
* Copy a fork's data, block by block.
*
@@ -355,7 +427,9 @@ RelationCopyStorage(SMgrRelation src, SMgrRelation dst,
/*
* We need to log the copied data in WAL iff WAL archiving/streaming is
- * enabled AND it's a permanent relation.
+ * enabled AND it's a permanent relation. This gives the same answer as
+ * "RelationNeedsWAL(rel) || copying_initfork", because we know the
+ * current operation created a new relfilenode.
*/
use_wal = XLogIsNeeded() &&
(relpersistence == RELPERSISTENCE_PERMANENT || copying_initfork);
@@ -397,24 +471,39 @@ RelationCopyStorage(SMgrRelation src, SMgrRelation dst,
}
/*
- * If the rel is WAL-logged, must fsync before commit. We use heap_sync
- * to ensure that the toast table gets fsync'd too. (For a temp or
- * unlogged rel we don't care since the data will be gone after a crash
- * anyway.)
- *
- * It's obvious that we must do this when not WAL-logging the copy. It's
- * less obvious that we have to do it even if we did WAL-log the copied
- * pages. The reason is that since we're copying outside shared buffers, a
- * CHECKPOINT occurring during the copy has no way to flush the previously
- * written data to disk (indeed it won't know the new rel even exists). A
- * crash later on would replay WAL from the checkpoint, therefore it
- * wouldn't replay our earlier WAL entries. If we do not fsync those pages
- * here, they might still not be on disk when the crash occurs.
+ * When we WAL-logged rel pages, we must nonetheless fsync them. The
+ * reason is that since we're copying outside shared buffers, a CHECKPOINT
+ * occurring during the copy has no way to flush the previously written
+ * data to disk (indeed it won't know the new rel even exists). A crash
+ * later on would replay WAL from the checkpoint, therefore it wouldn't
+ * replay our earlier WAL entries. If we do not fsync those pages here,
+ * they might still not be on disk when the crash occurs.
*/
- if (relpersistence == RELPERSISTENCE_PERMANENT || copying_initfork)
+ if (use_wal || copying_initfork)
smgrimmedsync(dst, forkNum);
}
+/*
+ * RelFileNodeSkippingWAL - check if a BM_PERMANENT relfilenode is using WAL
+ *
+ * Changes of certain relfilenodes must not write WAL; see "Skipping WAL for
+ * New RelFileNode" in src/backend/access/transam/README. Though it is
+ * known from Relation efficiently, this function is intended for the code
+ * paths not having access to Relation.
+ */
+bool
+RelFileNodeSkippingWAL(RelFileNode rnode)
+{
+ if (XLogIsNeeded())
+ return false; /* no permanent relfilenode skips WAL */
+
+ if (!pendingSyncHash ||
+ hash_search(pendingSyncHash, &rnode, HASH_FIND, NULL) == NULL)
+ return false;
+
+ return true;
+}
+
/*
* smgrDoPendingDeletes() -- Take care of relation deletes at end of xact.
*
@@ -492,6 +581,135 @@ smgrDoPendingDeletes(bool isCommit)
}
}
+/*
+ * smgrDoPendingSyncs() -- Take care of relation syncs at end of xact.
+ */
+void
+smgrDoPendingSyncs(bool isCommit)
+{
+ PendingRelDelete *pending;
+ int nrels = 0,
+ maxrels = 0;
+ SMgrRelation *srels = NULL;
+ HASH_SEQ_STATUS scan;
+ pendingSync *pendingsync;
+
+ if (XLogIsNeeded())
+ return; /* no relation can use this */
+
+ Assert(GetCurrentTransactionNestLevel() == 1);
+
+ if (!pendingSyncHash)
+ return; /* no relation needs sync */
+
+ /* Just throw away all pending syncs if any at rollback */
+ if (!isCommit)
+ {
+ pendingSyncHash = NULL;
+ return;
+ }
+
+ AssertPendingSyncs_RelationCache();
+
+ /* Skip syncing nodes that smgrDoPendingDeletes() will delete. */
+ for (pending = pendingDeletes; pending != NULL; pending = pending->next)
+ {
+ if (!pending->atCommit)
+ continue;
+
+ (void) hash_search(pendingSyncHash, (void *) &pending->relnode,
+ HASH_REMOVE, NULL);
+ }
+
+ hash_seq_init(&scan, pendingSyncHash);
+ while ((pendingsync = (pendingSync *) hash_seq_search(&scan)))
+ {
+ ForkNumber fork;
+ BlockNumber nblocks[MAX_FORKNUM + 1];
+ BlockNumber total_blocks = 0;
+ SMgrRelation srel;
+
+ srel = smgropen(pendingsync->rnode, InvalidBackendId);
+
+ /*
+ * We emit newpage WAL records for smaller relations.
+ *
+ * Small WAL records have a chance to be emitted along with other
+ * backends' WAL records. We emit WAL records instead of syncing for
+ * files that are smaller than a certain threshold, expecting faster
+ * commit. The threshold is defined by the GUC wal_skip_threshold.
+ */
+ for (fork = 0; fork <= MAX_FORKNUM; fork++)
+ {
+ if (smgrexists(srel, fork))
+ {
+ BlockNumber n = smgrnblocks(srel, fork);
+
+ /* we shouldn't come here for unlogged relations */
+ Assert(fork != INIT_FORKNUM);
+
+ nblocks[fork] = n;
+ total_blocks += n;
+ }
+ else
+ nblocks[fork] = InvalidBlockNumber;
+ }
+
+ /*
+ * Sync file or emit WAL records for its contents. Do file sync if
+ * the size is larger than the threshold or truncates may have removed
+ * blocks beyond the current size.
+ */
+ if (total_blocks * BLCKSZ / 1024 >= wal_skip_threshold ||
+ nblocks[MAIN_FORKNUM] < pendingsync->max_truncated)
+ {
+ /* allocate the initial array, or extend it, if needed */
+ if (maxrels == 0)
+ {
+ maxrels = 8;
+ srels = palloc(sizeof(SMgrRelation) * maxrels);
+ }
+ else if (maxrels <= nrels)
+ {
+ maxrels *= 2;
+ srels = repalloc(srels, sizeof(SMgrRelation) * maxrels);
+ }
+
+ srels[nrels++] = srel;
+ }
+ else
+ {
+ /* Emit WAL records for all blocks. The file is small enough. */
+ for (fork = 0; fork <= MAX_FORKNUM; fork++)
+ {
+ int n = nblocks[fork];
+ Relation rel;
+
+ if (!BlockNumberIsValid(n))
+ continue;
+
+ /*
+ * Emit WAL for the whole file. Unfortunately we don't know
+ * what kind of a page this is, so we have to log the full
+ * page including any unused space. ReadBufferExtended()
+ * counts some pgstat events; unfortunately, we discard them.
+ */
+ rel = CreateFakeRelcacheEntry(srel->smgr_rnode.node);
+ log_newpage_range(rel, fork, 0, n, false);
+ FreeFakeRelcacheEntry(rel);
+ }
+ }
+ }
+
+ pendingSyncHash = NULL;
+
+ if (nrels > 0)
+ {
+ smgrdosyncall(srels, nrels);
+ pfree(srels);
+ }
+}
+
/*
* smgrGetPendingDeletes() -- Get a list of non-temp relations to be deleted.
*
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index e9d7a7ff79..b836ccf2d6 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -1014,6 +1014,7 @@ swap_relation_files(Oid r1, Oid r2, bool target_is_pg_class,
relfilenode2;
Oid swaptemp;
char swptmpchr;
+ Relation rel1;
/* We need writable copies of both pg_class tuples. */
relRelation = table_open(RelationRelationId, RowExclusiveLock);
@@ -1173,6 +1174,15 @@ swap_relation_files(Oid r1, Oid r2, bool target_is_pg_class,
CacheInvalidateRelcacheByTuple(reltup2);
}
+ /*
+ * Recognize that rel1's relfilenode (swapped from rel2) is new in this
+ * subtransaction. Since the next step for rel2 is deletion, don't bother
+ * recording the newness of its relfilenode.
+ */
+ rel1 = relation_open(r1, NoLock);
+ RelationAssumeNewRelfilenode(rel1);
+ relation_close(rel1, NoLock);
+
/*
* Post alter hook for modified relations. The change to r2 is always
* internal, but r1 depends on the invocation context.
@@ -1489,7 +1499,7 @@ finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap,
/* Get the associated valid index to be renamed */
toastidx = toast_get_valid_index(newrel->rd_rel->reltoastrelid,
- AccessShareLock);
+ NoLock);
/* rename the toast table ... */
snprintf(NewToastName, NAMEDATALEN, "pg_toast_%u",
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 40a8ec1abd..f9acde56a5 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -2712,63 +2712,15 @@ CopyFrom(CopyState cstate)
RelationGetRelationName(cstate->rel))));
}
- /*----------
- * Check to see if we can avoid writing WAL
- *
- * If archive logging/streaming is not enabled *and* either
- * - table was created in same transaction as this COPY
- * - data is being written to relfilenode created in this transaction
- * then we can skip writing WAL. It's safe because if the transaction
- * doesn't commit, we'll discard the table (or the new relfilenode file).
- * If it does commit, we'll have done the table_finish_bulk_insert() at
- * the bottom of this routine first.
- *
- * As mentioned in comments in utils/rel.h, the in-same-transaction test
- * is not always set correctly, since in rare cases rd_newRelfilenodeSubid
- * can be cleared before the end of the transaction. The exact case is
- * when a relation sets a new relfilenode twice in same transaction, yet
- * the second one fails in an aborted subtransaction, e.g.
- *
- * BEGIN;
- * TRUNCATE t;
- * SAVEPOINT save;
- * TRUNCATE t;
- * ROLLBACK TO save;
- * COPY ...
- *
- * Also, if the target file is new-in-transaction, we assume that checking
- * FSM for free space is a waste of time, even if we must use WAL because
- * of archiving. This could possibly be wrong, but it's unlikely.
- *
- * The comments for table_tuple_insert and RelationGetBufferForTuple
- * specify that skipping WAL logging is only safe if we ensure that our
- * tuples do not go into pages containing tuples from any other
- * transactions --- but this must be the case if we have a new table or
- * new relfilenode, so we need no additional work to enforce that.
- *
- * We currently don't support this optimization if the COPY target is a
- * partitioned table as we currently only lazily initialize partition
- * information when routing the first tuple to the partition. We cannot
- * know at this stage if we can perform this optimization. It should be
- * possible to improve on this, but it does mean maintaining heap insert
- * option flags per partition and setting them when we first open the
- * partition.
- *
- * This optimization is not supported for relation types which do not
- * have any physical storage, with foreign tables and views using
- * INSTEAD OF triggers entering in this category. Partitioned tables
- * are not supported as per the description above.
- *----------
+ /*
+ * If the target file is new-in-transaction, we assume that checking FSM
+ * for free space is a waste of time. This could possibly be wrong, but
+ * it's unlikely.
*/
- /* createSubid is creation check, newRelfilenodeSubid is truncation check */
if (RELKIND_HAS_STORAGE(cstate->rel->rd_rel->relkind) &&
(cstate->rel->rd_createSubid != InvalidSubTransactionId ||
- cstate->rel->rd_newRelfilenodeSubid != InvalidSubTransactionId))
- {
+ cstate->rel->rd_firstRelfilenodeSubid != InvalidSubTransactionId))
ti_options |= TABLE_INSERT_SKIP_FSM;
- if (!XLogIsNeeded())
- ti_options |= TABLE_INSERT_SKIP_WAL;
- }
/*
* Optimize if new relfilenode was created in this subxact or one of its
diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c
index 9f387b5f5f..fe9a754782 100644
--- a/src/backend/commands/createas.c
+++ b/src/backend/commands/createas.c
@@ -552,16 +552,13 @@ intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
myState->rel = intoRelationDesc;
myState->reladdr = intoRelationAddr;
myState->output_cid = GetCurrentCommandId(true);
+ myState->ti_options = TABLE_INSERT_SKIP_FSM;
+ myState->bistate = GetBulkInsertState();
/*
- * We can skip WAL-logging the insertions, unless PITR or streaming
- * replication is in use. We can skip the FSM in any case.
+ * Valid smgr_targblock implies something already wrote to the relation.
+ * This may be harmless, but this function hasn't planned for it.
*/
- myState->ti_options = TABLE_INSERT_SKIP_FSM |
- (XLogIsNeeded() ? 0 : TABLE_INSERT_SKIP_WAL);
- myState->bistate = GetBulkInsertState();
-
- /* Not using WAL requires smgr_targblock be initially invalid */
Assert(RelationGetTargetBlock(intoRelationDesc) == InvalidBlockNumber);
}
diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c
index 1ee37c1aeb..ea1d0fc850 100644
--- a/src/backend/commands/matview.c
+++ b/src/backend/commands/matview.c
@@ -457,17 +457,13 @@ transientrel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
*/
myState->transientrel = transientrel;
myState->output_cid = GetCurrentCommandId(true);
-
- /*
- * We can skip WAL-logging the insertions, unless PITR or streaming
- * replication is in use. We can skip the FSM in any case.
- */
myState->ti_options = TABLE_INSERT_SKIP_FSM | TABLE_INSERT_FROZEN;
- if (!XLogIsNeeded())
- myState->ti_options |= TABLE_INSERT_SKIP_WAL;
myState->bistate = GetBulkInsertState();
- /* Not using WAL requires smgr_targblock be initially invalid */
+ /*
+ * Valid smgr_targblock implies something already wrote to the relation.
+ * This may be harmless, but this function hasn't planned for it.
+ */
Assert(RelationGetTargetBlock(transientrel) == InvalidBlockNumber);
}
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 30b72b6297..1b8e38d3aa 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -5007,19 +5007,14 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap, LOCKMODE lockmode)
newrel = NULL;
/*
- * Prepare a BulkInsertState and options for table_tuple_insert. Because
- * we're building a new heap, we can skip WAL-logging and fsync it to disk
- * at the end instead (unless WAL-logging is required for archiving or
- * streaming replication). The FSM is empty too, so don't bother using it.
+ * Prepare a BulkInsertState and options for table_tuple_insert. The FSM
+ * is empty, so don't bother using it.
*/
if (newrel)
{
mycid = GetCurrentCommandId(true);
bistate = GetBulkInsertState();
-
ti_options = TABLE_INSERT_SKIP_FSM;
- if (!XLogIsNeeded())
- ti_options |= TABLE_INSERT_SKIP_WAL;
}
else
{
@@ -12901,6 +12896,8 @@ ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode)
table_close(pg_class, RowExclusiveLock);
+ RelationAssumeNewRelfilenode(rel);
+
relation_close(rel, NoLock);
/* Make sure the reltablespace change is visible */
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index aba3960481..73c38757fa 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -66,7 +66,7 @@
#define BUF_WRITTEN 0x01
#define BUF_REUSABLE 0x02
-#define DROP_RELS_BSEARCH_THRESHOLD 20
+#define RELS_BSEARCH_THRESHOLD 20
typedef struct PrivateRefCountEntry
{
@@ -105,6 +105,19 @@ typedef struct CkptTsStatus
int index;
} CkptTsStatus;
+/*
+ * Type for array used to sort SMgrRelations
+ *
+ * FlushRelationsAllBuffers shares the same comparator function with
+ * DropRelFileNodesAllBuffers. Pointer to this struct and RelFileNode must be
+ * compatible.
+ */
+typedef struct SMgrSortArray
+{
+ RelFileNode rnode; /* This must be the first member */
+ SMgrRelation srel;
+} SMgrSortArray;
+
/* GUC variables */
bool zero_damaged_pages = false;
int bgwriter_lru_maxpages = 100;
@@ -3043,7 +3056,7 @@ DropRelFileNodesAllBuffers(RelFileNodeBackend *rnodes, int nnodes)
* an exactly determined value, as it depends on many factors (CPU and RAM
* speeds, amount of shared buffers etc.).
*/
- use_bsearch = n > DROP_RELS_BSEARCH_THRESHOLD;
+ use_bsearch = n > RELS_BSEARCH_THRESHOLD;
/* sort the list of rnodes if necessary */
if (use_bsearch)
@@ -3293,6 +3306,104 @@ FlushRelationBuffers(Relation rel)
}
}
+/* ---------------------------------------------------------------------
+ * FlushRelationsAllBuffers
+ *
+ * This function flushes out of the buffer pool all the pages of all
+ * forks of the specified smgr relations. It's equivalent to calling
+ * FlushRelationBuffers once per fork per relation. The relations are
+ * assumed not to use local buffers.
+ * --------------------------------------------------------------------
+ */
+void
+FlushRelationsAllBuffers(SMgrRelation *smgrs, int nrels)
+{
+ int i;
+ SMgrSortArray *srels;
+ bool use_bsearch;
+
+ if (nrels == 0)
+ return;
+
+ /* fill-in array for qsort */
+ srels = palloc(sizeof(SMgrSortArray) * nrels);
+
+ for (i = 0; i < nrels; i++)
+ {
+ Assert(!RelFileNodeBackendIsTemp(smgrs[i]->smgr_rnode));
+
+ srels[i].rnode = smgrs[i]->smgr_rnode.node;
+ srels[i].srel = smgrs[i];
+ }
+
+ /*
+ * Save the bsearch overhead for low number of relations to sync. See
+ * DropRelFileNodesAllBuffers for details.
+ */
+ use_bsearch = nrels > RELS_BSEARCH_THRESHOLD;
+
+ /* sort the list of SMgrRelations if necessary */
+ if (use_bsearch)
+ pg_qsort(srels, nrels, sizeof(SMgrSortArray), rnode_comparator);
+
+ /* Make sure we can handle the pin inside the loop */
+ ResourceOwnerEnlargeBuffers(CurrentResourceOwner);
+
+ for (i = 0; i < NBuffers; i++)
+ {
+ SMgrSortArray *srelent = NULL;
+ BufferDesc *bufHdr = GetBufferDescriptor(i);
+ uint32 buf_state;
+
+ /*
+ * As in DropRelFileNodeBuffers, an unlocked precheck should be safe
+ * and saves some cycles.
+ */
+
+ if (!use_bsearch)
+ {
+ int j;
+
+ for (j = 0; j < nrels; j++)
+ {
+ if (RelFileNodeEquals(bufHdr->tag.rnode, srels[j].rnode))
+ {
+ srelent = &srels[j];
+ break;
+ }
+ }
+
+ }
+ else
+ {
+ srelent = bsearch((const void *) &(bufHdr->tag.rnode),
+ srels, nrels, sizeof(SMgrSortArray),
+ rnode_comparator);
+ }
+
+ /* buffer doesn't belong to any of the given relfilenodes; skip it */
+ if (srelent == NULL)
+ continue;
+
+ ReservePrivateRefCountEntry();
+
+ buf_state = LockBufHdr(bufHdr);
+ if (RelFileNodeEquals(bufHdr->tag.rnode, srelent->rnode) &&
+ (buf_state & (BM_VALID | BM_DIRTY)) == (BM_VALID | BM_DIRTY))
+ {
+ PinBuffer_Locked(bufHdr);
+ LWLockAcquire(BufferDescriptorGetContentLock(bufHdr), LW_SHARED);
+ FlushBuffer(bufHdr, srelent->srel);
+ LWLockRelease(BufferDescriptorGetContentLock(bufHdr));
+ UnpinBuffer(bufHdr, true);
+ }
+ else
+ UnlockBufHdr(bufHdr, buf_state);
+ }
+
+ pfree(srels);
+}
+
/* ---------------------------------------------------------------------
* FlushDatabaseBuffers
*
@@ -3494,13 +3605,15 @@ MarkBufferDirtyHint(Buffer buffer, bool buffer_std)
(pg_atomic_read_u32(&bufHdr->state) & BM_PERMANENT))
{
/*
- * If we're in recovery we cannot dirty a page because of a hint.
- * We can set the hint, just not dirty the page as a result so the
- * hint is lost when we evict the page or shutdown.
+ * If we must not write WAL, due to a relfilenode-specific
+ * condition or being in recovery, don't dirty the page. We can
+ * set the hint, just not dirty the page as a result so the hint
+ * is lost when we evict the page or shutdown.
*
* See src/backend/storage/page/README for longer discussion.
*/
- if (RecoveryInProgress())
+ if (RecoveryInProgress() ||
+ RelFileNodeSkippingWAL(bufHdr->tag.rnode))
return;
/*
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 56dba09299..8f98f665c5 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -587,6 +587,18 @@ LockHeldByMe(const LOCKTAG *locktag, LOCKMODE lockmode)
return (locallock && locallock->nLocks > 0);
}
+#ifdef USE_ASSERT_CHECKING
+/*
+ * GetLockMethodLocalHash -- return the hash of local locks, for modules that
+ * evaluate assertions based on all locks held.
+ */
+HTAB *
+GetLockMethodLocalHash(void)
+{
+ return LockMethodLocalHash;
+}
+#endif
+
/*
* LockHasWaiters -- look up 'locktag' and check if releasing this
* lock would wake up other processes waiting for it.
diff --git a/src/backend/storage/smgr/md.c b/src/backend/storage/smgr/md.c
index 85b7115400..e28c5a49a8 100644
--- a/src/backend/storage/smgr/md.c
+++ b/src/backend/storage/smgr/md.c
@@ -248,11 +248,10 @@ mdcreate(SMgrRelation reln, ForkNumber forkNum, bool isRedo)
* During replay, we would delete the file and then recreate it, which is fine
* if the contents of the file were repopulated by subsequent WAL entries.
* But if we didn't WAL-log insertions, but instead relied on fsyncing the
- * file after populating it (as for instance CLUSTER and CREATE INDEX do),
- * the contents of the file would be lost forever. By leaving the empty file
- * until after the next checkpoint, we prevent reassignment of the relfilenode
- * number until it's safe, because relfilenode assignment skips over any
- * existing file.
+ * file after populating it (as we do at wal_level=minimal), the contents of
+ * the file would be lost forever. By leaving the empty file until after the
+ * next checkpoint, we prevent reassignment of the relfilenode number until
+ * it's safe, because relfilenode assignment skips over any existing file.
*
* We do not need to go through this dance for temp relations, though, because
* we never make WAL entries for temp rels, and so a temp rel poses no threat
@@ -877,12 +876,18 @@ mdtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks)
* mdimmedsync() -- Immediately sync a relation to stable storage.
*
* Note that only writes already issued are synced; this routine knows
- * nothing of dirty buffers that may exist inside the buffer manager.
+ * nothing of dirty buffers that may exist inside the buffer manager. We
+ * sync active and inactive segments; smgrDoPendingSyncs() relies on this.
+ * Consider a relation skipping WAL. Suppose a checkpoint syncs blocks of
+ * some segment, then mdtruncate() renders that segment inactive. If we
+ * crash before the next checkpoint syncs the newly-inactive segment, that
+ * segment may survive recovery, reintroducing unwanted data into the table.
*/
void
mdimmedsync(SMgrRelation reln, ForkNumber forknum)
{
int segno;
+ int min_inactive_seg;
/*
* NOTE: mdnblocks makes sure we have opened all active segments, so that
@@ -890,7 +895,16 @@ mdimmedsync(SMgrRelation reln, ForkNumber forknum)
*/
mdnblocks(reln, forknum);
- segno = reln->md_num_open_segs[forknum];
+ min_inactive_seg = segno = reln->md_num_open_segs[forknum];
+
+ /*
+ * Temporarily open inactive segments, then close them after sync. There
+ * may be some inactive segments left opened after fsync() error, but that
+ * is harmless. We don't bother to clean them up and take a risk of
+ * further trouble. The next mdclose() will soon close them.
+ */
+ while (_mdfd_openseg(reln, forknum, segno, 0) != NULL)
+ segno++;
while (segno > 0)
{
@@ -901,6 +915,14 @@ mdimmedsync(SMgrRelation reln, ForkNumber forknum)
(errcode_for_file_access(),
errmsg("could not fsync file \"%s\": %m",
FilePathName(v->mdfd_vfd))));
+
+ /* Close inactive segments immediately */
+ if (segno > min_inactive_seg)
+ {
+ FileClose(v->mdfd_vfd);
+ _fdvec_resize(reln, forknum, segno - 1);
+ }
+
segno--;
}
}
diff --git a/src/backend/storage/smgr/smgr.c b/src/backend/storage/smgr/smgr.c
index 360b5bf5bf..72c9696ad1 100644
--- a/src/backend/storage/smgr/smgr.c
+++ b/src/backend/storage/smgr/smgr.c
@@ -388,6 +388,41 @@ smgrdounlink(SMgrRelation reln, bool isRedo)
smgrsw[which].smgr_unlink(rnode, InvalidForkNumber, isRedo);
}
+/*
+ * smgrdosyncall() -- Immediately sync all forks of all given relations
+ *
+ * All forks of all given relations are synced out to the store.
+ *
+ * This is equivalent to FlushRelationBuffers() for each smgr relation,
+ * then calling smgrimmedsync() for all forks of each relation, but it's
+ * significantly quicker so should be preferred when possible.
+ */
+void
+smgrdosyncall(SMgrRelation *rels, int nrels)
+{
+ int i = 0;
+ ForkNumber forknum;
+
+ if (nrels == 0)
+ return;
+
+ FlushRelationsAllBuffers(rels, nrels);
+
+ /*
+ * Sync the physical file(s).
+ */
+ for (i = 0; i < nrels; i++)
+ {
+ int which = rels[i]->smgr_which;
+
+ for (forknum = 0; forknum <= MAX_FORKNUM; forknum++)
+ {
+ if (smgrsw[which].smgr_exists(rels[i], forknum))
+ smgrsw[which].smgr_immedsync(rels[i], forknum);
+ }
+ }
+}
+
/*
* smgrdounlinkall() -- Immediately unlink all forks of all given relations
*
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index df025a5a30..0ac72572e3 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -257,6 +257,9 @@ static void RelationReloadIndexInfo(Relation relation);
static void RelationReloadNailed(Relation relation);
static void RelationFlushRelation(Relation relation);
static void RememberToFreeTupleDescAtEOX(TupleDesc td);
+#ifdef USE_ASSERT_CHECKING
+static void AssertPendingSyncConsistency(Relation relation);
+#endif
static void AtEOXact_cleanup(Relation relation, bool isCommit);
static void AtEOSubXact_cleanup(Relation relation, bool isCommit,
SubTransactionId mySubid, SubTransactionId parentSubid);
@@ -1090,6 +1093,7 @@ RelationBuildDesc(Oid targetRelId, bool insertIt)
relation->rd_isnailed = false;
relation->rd_createSubid = InvalidSubTransactionId;
relation->rd_newRelfilenodeSubid = InvalidSubTransactionId;
+ relation->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
switch (relation->rd_rel->relpersistence)
{
case RELPERSISTENCE_UNLOGGED:
@@ -1814,6 +1818,7 @@ formrdesc(const char *relationName, Oid relationReltype,
relation->rd_isnailed = true;
relation->rd_createSubid = InvalidSubTransactionId;
relation->rd_newRelfilenodeSubid = InvalidSubTransactionId;
+ relation->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
relation->rd_backend = InvalidBackendId;
relation->rd_islocaltemp = false;
@@ -2021,6 +2026,7 @@ RelationIdGetRelation(Oid relationId)
rd = RelationBuildDesc(relationId, true);
if (RelationIsValid(rd))
RelationIncrementReferenceCount(rd);
+
return rd;
}
@@ -2089,7 +2095,7 @@ RelationClose(Relation relation)
#ifdef RELCACHE_FORCE_RELEASE
if (RelationHasReferenceCountZero(relation) &&
relation->rd_createSubid == InvalidSubTransactionId &&
- relation->rd_newRelfilenodeSubid == InvalidSubTransactionId)
+ relation->rd_firstRelfilenodeSubid == InvalidSubTransactionId)
RelationClearRelation(relation, false);
#endif
}
@@ -2505,13 +2511,13 @@ RelationClearRelation(Relation relation, bool rebuild)
* problem.
*
* When rebuilding an open relcache entry, we must preserve ref count,
- * rd_createSubid/rd_newRelfilenodeSubid, and rd_toastoid state. Also
- * attempt to preserve the pg_class entry (rd_rel), tupledesc,
- * rewrite-rule, partition key, and partition descriptor substructures
- * in place, because various places assume that these structures won't
- * move while they are working with an open relcache entry. (Note:
- * the refcount mechanism for tupledescs might someday allow us to
- * remove this hack for the tupledesc.)
+ * rd_*Subid, and rd_toastoid state. Also attempt to preserve the
+ * pg_class entry (rd_rel), tupledesc, rewrite-rule, partition key,
+ * and partition descriptor substructures in place, because various
+ * places assume that these structures won't move while they are
+ * working with an open relcache entry. (Note: the refcount
+ * mechanism for tupledescs might someday allow us to remove this hack
+ * for the tupledesc.)
*
* Note that this process does not touch CurrentResourceOwner; which
* is good because whatever ref counts the entry may have do not
@@ -2591,6 +2597,7 @@ RelationClearRelation(Relation relation, bool rebuild)
/* creation sub-XIDs must be preserved */
SWAPFIELD(SubTransactionId, rd_createSubid);
SWAPFIELD(SubTransactionId, rd_newRelfilenodeSubid);
+ SWAPFIELD(SubTransactionId, rd_firstRelfilenodeSubid);
/* un-swap rd_rel pointers, swap contents instead */
SWAPFIELD(Form_pg_class, rd_rel);
/* ... but actually, we don't have to update newrel->rd_rel */
@@ -2669,12 +2676,12 @@ static void
RelationFlushRelation(Relation relation)
{
if (relation->rd_createSubid != InvalidSubTransactionId ||
- relation->rd_newRelfilenodeSubid != InvalidSubTransactionId)
+ relation->rd_firstRelfilenodeSubid != InvalidSubTransactionId)
{
/*
* New relcache entries are always rebuilt, not flushed; else we'd
- * forget the "new" status of the relation, which is a useful
- * optimization to have. Ditto for the new-relfilenode status.
+ * forget the "new" status of the relation. Ditto for the
+ * new-relfilenode status.
*
* The rel could have zero refcnt here, so temporarily increment the
* refcnt to ensure it's safe to rebuild it. We can assume that the
@@ -2754,11 +2761,10 @@ RelationCacheInvalidateEntry(Oid relationId)
* relation cache and re-read relation mapping data.
*
* This is currently used only to recover from SI message buffer overflow,
- * so we do not touch new-in-transaction relations; they cannot be targets
- * of cross-backend SI updates (and our own updates now go through a
- * separate linked list that isn't limited by the SI message buffer size).
- * Likewise, we need not discard new-relfilenode-in-transaction hints,
- * since any invalidation of those would be a local event.
+ * so we do not touch relations having new-in-transaction relfilenodes; they
+ * cannot be targets of cross-backend SI updates (and our own updates now go
+ * through a separate linked list that isn't limited by the SI message
+ * buffer size).
*
* We do this in two phases: the first pass deletes deletable items, and
* the second one rebuilds the rebuildable items. This is essential for
@@ -2809,7 +2815,7 @@ RelationCacheInvalidate(void)
* pending invalidations.
*/
if (relation->rd_createSubid != InvalidSubTransactionId ||
- relation->rd_newRelfilenodeSubid != InvalidSubTransactionId)
+ relation->rd_firstRelfilenodeSubid != InvalidSubTransactionId)
continue;
relcacheInvalsReceived++;
@@ -2921,6 +2927,78 @@ RememberToFreeTupleDescAtEOX(TupleDesc td)
EOXactTupleDescArray[NextEOXactTupleDescNum++] = td;
}
+#ifdef USE_ASSERT_CHECKING
+static void
+AssertPendingSyncConsistency(Relation relation)
+{
+ bool relcache_verdict =
+ relation->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT &&
+ ((relation->rd_createSubid != InvalidSubTransactionId &&
+ RELKIND_HAS_STORAGE(relation->rd_rel->relkind)) ||
+ relation->rd_firstRelfilenodeSubid != InvalidSubTransactionId);
+
+ Assert(relcache_verdict == RelFileNodeSkippingWAL(relation->rd_node));
+}
+
+/*
+ * AssertPendingSyncs_RelationCache
+ *
+ * Assert that relcache.c and storage.c agree on whether to skip WAL.
+ *
+ * This consistently detects relcache.c skipping WAL while storage.c is not
+ * skipping WAL. It often fails to detect the reverse error, because
+ * invalidation will have destroyed the relcache entry. It will detect the
+ * reverse error if something opens the relation after the DDL.
+ */
+void
+AssertPendingSyncs_RelationCache(void)
+{
+ HASH_SEQ_STATUS status;
+ LOCALLOCK *locallock;
+ Relation *rels;
+ int maxrels;
+ int nrels;
+ RelIdCacheEnt *idhentry;
+ int i;
+
+ /* open every relation that this transaction has locked */
+ PushActiveSnapshot(GetTransactionSnapshot());
+ maxrels = 1;
+ rels = palloc(maxrels * sizeof(*rels));
+ nrels = 0;
+ hash_seq_init(&status, GetLockMethodLocalHash());
+ while ((locallock = (LOCALLOCK *) hash_seq_search(&status)) != NULL)
+ {
+ Oid relid;
+ Relation r;
+
+ if (locallock->nLocks <= 0)
+ continue;
+ if ((LockTagType) locallock->tag.lock.locktag_type !=
+ LOCKTAG_RELATION)
+ continue;
+ relid = ObjectIdGetDatum(locallock->tag.lock.locktag_field2);
+ r = RelationIdGetRelation(relid);
+ if (r == NULL)
+ continue;
+ if (nrels >= maxrels)
+ {
+ maxrels *= 2;
+ rels = repalloc(rels, maxrels * sizeof(*rels));
+ }
+ rels[nrels++] = r;
+ }
+
+ hash_seq_init(&status, RelationIdCache);
+ while ((idhentry = (RelIdCacheEnt *) hash_seq_search(&status)) != NULL)
+ AssertPendingSyncConsistency(idhentry->reldesc);
+
+ for (i = 0; i < nrels; i++)
+ RelationClose(rels[i]);
+ PopActiveSnapshot();
+}
+#endif
+
/*
* AtEOXact_RelationCache
*
@@ -3032,10 +3110,7 @@ AtEOXact_cleanup(Relation relation, bool isCommit)
*
* During commit, reset the flag to zero, since we are now out of the
* creating transaction. During abort, simply delete the relcache entry
- * --- it isn't interesting any longer. (NOTE: if we have forgotten the
- * new-ness of a new relation due to a forced cache flush, the entry will
- * get deleted anyway by shared-cache-inval processing of the aborted
- * pg_class insertion.)
+ * --- it isn't interesting any longer.
*/
if (relation->rd_createSubid != InvalidSubTransactionId)
{
@@ -3063,9 +3138,10 @@ AtEOXact_cleanup(Relation relation, bool isCommit)
}
/*
- * Likewise, reset the hint about the relfilenode being new.
+ * Likewise, reset any record of the relfilenode being new.
*/
relation->rd_newRelfilenodeSubid = InvalidSubTransactionId;
+ relation->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
}
/*
@@ -3157,7 +3233,7 @@ AtEOSubXact_cleanup(Relation relation, bool isCommit,
}
/*
- * Likewise, update or drop any new-relfilenode-in-subtransaction hint.
+ * Likewise, update or drop any new-relfilenode-in-subtransaction record.
*/
if (relation->rd_newRelfilenodeSubid == mySubid)
{
@@ -3166,6 +3242,14 @@ AtEOSubXact_cleanup(Relation relation, bool isCommit,
else
relation->rd_newRelfilenodeSubid = InvalidSubTransactionId;
}
+
+ if (relation->rd_firstRelfilenodeSubid == mySubid)
+ {
+ if (isCommit)
+ relation->rd_firstRelfilenodeSubid = parentSubid;
+ else
+ relation->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
+ }
}
@@ -3255,6 +3339,7 @@ RelationBuildLocalRelation(const char *relname,
/* it's being created in this transaction */
rel->rd_createSubid = GetCurrentSubTransactionId();
rel->rd_newRelfilenodeSubid = InvalidSubTransactionId;
+ rel->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
/*
* create a new tuple descriptor from the one passed in. We do this
@@ -3552,14 +3637,29 @@ RelationSetNewRelfilenode(Relation relation, char persistence)
*/
CommandCounterIncrement();
- /*
- * Mark the rel as having been given a new relfilenode in the current
- * (sub) transaction. This is a hint that can be used to optimize later
- * operations on the rel in the same transaction.
- */
+ RelationAssumeNewRelfilenode(relation);
+}
+
+/*
+ * RelationAssumeNewRelfilenode
+ *
+ * Code that modifies pg_class.reltablespace or pg_class.relfilenode must call
+ * this. The call shall precede any code that might insert WAL records whose
+ * replay would modify bytes in the new RelFileNode, and the call shall follow
+ * any WAL modifying bytes in the prior RelFileNode. See struct RelationData.
+ * Ideally, call this as near as possible to the CommandCounterIncrement()
+ * that makes the pg_class change visible (before it or after it); that
+ * minimizes the chance of future development adding a forbidden WAL insertion
+ * between RelationAssumeNewRelfilenode() and CommandCounterIncrement().
+ */
+void
+RelationAssumeNewRelfilenode(Relation relation)
+{
relation->rd_newRelfilenodeSubid = GetCurrentSubTransactionId();
+ if (relation->rd_firstRelfilenodeSubid == InvalidSubTransactionId)
+ relation->rd_firstRelfilenodeSubid = relation->rd_newRelfilenodeSubid;
- /* Flag relation as needing eoxact cleanup (to remove the hint) */
+ /* Flag relation as needing eoxact cleanup (to clear these fields) */
EOXactListAdd(relation);
}
@@ -5625,6 +5725,7 @@ load_relcache_init_file(bool shared)
rel->rd_fkeylist = NIL;
rel->rd_createSubid = InvalidSubTransactionId;
rel->rd_newRelfilenodeSubid = InvalidSubTransactionId;
+ rel->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
rel->rd_amcache = NULL;
MemSet(&rel->pgstat_info, 0, sizeof(rel->pgstat_info));
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index e44f71e991..e69b62e22d 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -36,6 +36,7 @@
#include "access/xlog_internal.h"
#include "catalog/namespace.h"
#include "catalog/pg_authid.h"
+#include "catalog/storage.h"
#include "commands/async.h"
#include "commands/prepare.h"
#include "commands/trigger.h"
@@ -2674,6 +2675,18 @@ static struct config_int ConfigureNamesInt[] =
NULL, NULL, NULL
},
+ {
+ {"wal_skip_threshold", PGC_USERSET, RESOURCES_DISK,
+ gettext_noop("Size of new file to fsync instead of writing WAL."),
+ NULL,
+ GUC_UNIT_KB
+ },
+ &wal_skip_threshold,
+ 2048,
+ 0, MAX_KILOBYTES,
+ NULL, NULL, NULL
+ },
+
{
{"max_wal_senders", PGC_POSTMASTER, REPLICATION_SENDING,
gettext_noop("Sets the maximum number of simultaneously running WAL sender processes."),
diff --git a/src/include/access/gist_private.h b/src/include/access/gist_private.h
index 18f2b0d98e..4bfc628000 100644
--- a/src/include/access/gist_private.h
+++ b/src/include/access/gist_private.h
@@ -455,6 +455,8 @@ extern XLogRecPtr gistXLogSplit(bool page_is_leaf,
BlockNumber origrlink, GistNSN oldnsn,
Buffer leftchild, bool markfollowright);
+extern XLogRecPtr gistXLogAssignLSN(void);
+
/* gistget.c */
extern bool gistgettuple(IndexScanDesc scan, ScanDirection dir);
extern int64 gistgetbitmap(IndexScanDesc scan, TIDBitmap *tbm);
diff --git a/src/include/access/gistxlog.h b/src/include/access/gistxlog.h
index 55fc843d3a..673afee1e1 100644
--- a/src/include/access/gistxlog.h
+++ b/src/include/access/gistxlog.h
@@ -26,6 +26,7 @@
/* #define XLOG_GIST_INSERT_COMPLETE 0x40 */ /* not used anymore */
/* #define XLOG_GIST_CREATE_INDEX 0x50 */ /* not used anymore */
#define XLOG_GIST_PAGE_DELETE 0x60
+#define XLOG_GIST_ASSIGN_LSN 0x70 /* nop, assign new LSN */
/*
* Backup Blk 0: updated page.
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h
index 00a17f5f71..14f096d037 100644
--- a/src/include/access/heapam.h
+++ b/src/include/access/heapam.h
@@ -31,7 +31,6 @@
/* "options" flag bits for heap_insert */
-#define HEAP_INSERT_SKIP_WAL TABLE_INSERT_SKIP_WAL
#define HEAP_INSERT_SKIP_FSM TABLE_INSERT_SKIP_FSM
#define HEAP_INSERT_FROZEN TABLE_INSERT_FROZEN
#define HEAP_INSERT_NO_LOGICAL TABLE_INSERT_NO_LOGICAL
@@ -168,8 +167,6 @@ extern void simple_heap_delete(Relation relation, ItemPointer tid);
extern void simple_heap_update(Relation relation, ItemPointer otid,
HeapTuple tup);
-extern void heap_sync(Relation relation);
-
extern TransactionId heap_compute_xid_horizon_for_tuples(Relation rel,
ItemPointerData *items,
int nitems);
diff --git a/src/include/access/rewriteheap.h b/src/include/access/rewriteheap.h
index fb2902bd69..e6d7fa1e65 100644
--- a/src/include/access/rewriteheap.h
+++ b/src/include/access/rewriteheap.h
@@ -23,7 +23,7 @@ typedef struct RewriteStateData *RewriteState;
extern RewriteState begin_heap_rewrite(Relation OldHeap, Relation NewHeap,
TransactionId OldestXmin, TransactionId FreezeXid,
- MultiXactId MultiXactCutoff, bool use_wal);
+ MultiXactId MultiXactCutoff);
extern void end_heap_rewrite(RewriteState state);
extern void rewrite_heap_tuple(RewriteState state, HeapTuple oldTuple,
HeapTuple newTuple);
diff --git a/src/include/access/tableam.h b/src/include/access/tableam.h
index 696451f728..6547099e84 100644
--- a/src/include/access/tableam.h
+++ b/src/include/access/tableam.h
@@ -127,7 +127,7 @@ typedef struct TM_FailureData
} TM_FailureData;
/* "options" flag bits for table_tuple_insert */
-#define TABLE_INSERT_SKIP_WAL 0x0001
+/* TABLE_INSERT_SKIP_WAL was 0x0001; RelationNeedsWAL() now governs */
#define TABLE_INSERT_SKIP_FSM 0x0002
#define TABLE_INSERT_FROZEN 0x0004
#define TABLE_INSERT_NO_LOGICAL 0x0008
@@ -409,9 +409,8 @@ typedef struct TableAmRoutine
/*
* Perform operations necessary to complete insertions made via
- * tuple_insert and multi_insert with a BulkInsertState specified. This
- * may for example be used to flush the relation, when the
- * TABLE_INSERT_SKIP_WAL option was used.
+ * tuple_insert and multi_insert with a BulkInsertState specified. In-tree
+ * access methods ceased to use this.
*
* Typically callers of tuple_insert and multi_insert will just pass all
* the flags that apply to them, and each AM has to decide which of them
@@ -1105,10 +1104,6 @@ table_compute_xid_horizon_for_tuples(Relation rel,
* The options bitmask allows the caller to specify options that may change the
* behaviour of the AM. The AM will ignore options that it does not support.
*
- * If the TABLE_INSERT_SKIP_WAL option is specified, the new tuple doesn't
- * need to be logged to WAL, even for a non-temp relation. It is the AMs
- * choice whether this optimization is supported.
- *
* If the TABLE_INSERT_SKIP_FSM option is specified, AMs are free to not reuse
* free space in the relation. This can save some cycles when we know the
* relation is new and doesn't contain useful amounts of free space.
@@ -1328,9 +1323,7 @@ table_tuple_lock(Relation rel, ItemPointer tid, Snapshot snapshot,
/*
* Perform operations necessary to complete insertions made via
- * tuple_insert and multi_insert with a BulkInsertState specified. This
- * e.g. may e.g. used to flush the relation when inserting with
- * TABLE_INSERT_SKIP_WAL specified.
+ * tuple_insert and multi_insert with a BulkInsertState specified.
*/
static inline void
table_finish_bulk_insert(Relation rel, int options)
diff --git a/src/include/catalog/storage.h b/src/include/catalog/storage.h
index 048003c25e..bd37bf311c 100644
--- a/src/include/catalog/storage.h
+++ b/src/include/catalog/storage.h
@@ -19,18 +19,24 @@
#include "storage/smgr.h"
#include "utils/relcache.h"
+/* GUC variables */
+extern int wal_skip_threshold;
+
extern SMgrRelation RelationCreateStorage(RelFileNode rnode, char relpersistence);
extern void RelationDropStorage(Relation rel);
extern void RelationPreserveStorage(RelFileNode rnode, bool atCommit);
+extern void RelationPreTruncate(Relation rel);
extern void RelationTruncate(Relation rel, BlockNumber nblocks);
extern void RelationCopyStorage(SMgrRelation src, SMgrRelation dst,
ForkNumber forkNum, char relpersistence);
+extern bool RelFileNodeSkippingWAL(RelFileNode rnode);
/*
* These functions used to be in storage/smgr/smgr.c, which explains the
* naming
*/
extern void smgrDoPendingDeletes(bool isCommit);
+extern void smgrDoPendingSyncs(bool isCommit);
extern int smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr);
extern void AtSubCommit_smgr(void);
extern void AtSubAbort_smgr(void);
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index 73c7e9ba38..292d440eaf 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -49,6 +49,9 @@ typedef enum
/* forward declared, to avoid having to expose buf_internals.h here */
struct WritebackContext;
+/* forward declared, to avoid including smgr.h here */
+struct SMgrRelationData;
+
/* in globals.c ... this duplicates miscadmin.h */
extern PGDLLIMPORT int NBuffers;
@@ -189,6 +192,7 @@ extern BlockNumber RelationGetNumberOfBlocksInFork(Relation relation,
ForkNumber forkNum);
extern void FlushOneBuffer(Buffer buffer);
extern void FlushRelationBuffers(Relation rel);
+extern void FlushRelationsAllBuffers(struct SMgrRelationData **smgrs, int nrels);
extern void FlushDatabaseBuffers(Oid dbid);
extern void DropRelFileNodeBuffers(RelFileNodeBackend rnode, ForkNumber *forkNum,
int nforks, BlockNumber *firstDelBlock);
diff --git a/src/include/storage/lock.h b/src/include/storage/lock.h
index bb8e4e6e5b..8c180094f0 100644
--- a/src/include/storage/lock.h
+++ b/src/include/storage/lock.h
@@ -544,6 +544,9 @@ extern void LockReleaseSession(LOCKMETHODID lockmethodid);
extern void LockReleaseCurrentOwner(LOCALLOCK **locallocks, int nlocks);
extern void LockReassignCurrentOwner(LOCALLOCK **locallocks, int nlocks);
extern bool LockHeldByMe(const LOCKTAG *locktag, LOCKMODE lockmode);
+#ifdef USE_ASSERT_CHECKING
+extern HTAB *GetLockMethodLocalHash(void);
+#endif
extern bool LockHasWaiters(const LOCKTAG *locktag,
LOCKMODE lockmode, bool sessionLock);
extern VirtualTransactionId *GetLockConflicts(const LOCKTAG *locktag,
diff --git a/src/include/storage/smgr.h b/src/include/storage/smgr.h
index 243822137c..79dfe0e373 100644
--- a/src/include/storage/smgr.h
+++ b/src/include/storage/smgr.h
@@ -89,6 +89,7 @@ extern void smgrcloseall(void);
extern void smgrclosenode(RelFileNodeBackend rnode);
extern void smgrcreate(SMgrRelation reln, ForkNumber forknum, bool isRedo);
extern void smgrdounlink(SMgrRelation reln, bool isRedo);
+extern void smgrdosyncall(SMgrRelation *rels, int nrels);
extern void smgrdounlinkall(SMgrRelation *rels, int nrels, bool isRedo);
extern void smgrextend(SMgrRelation reln, ForkNumber forknum,
BlockNumber blocknum, char *buffer, bool skipFsync);
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 44ed04dd3f..ad72a8b910 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -64,22 +64,40 @@ typedef struct RelationData
* rd_replidindex) */
bool rd_statvalid; /* is rd_statlist valid? */
- /*
+ /*----------
* rd_createSubid is the ID of the highest subtransaction the rel has
- * survived into; or zero if the rel was not created in the current top
- * transaction. This can be now be relied on, whereas previously it could
- * be "forgotten" in earlier releases. Likewise, rd_newRelfilenodeSubid is
- * the ID of the highest subtransaction the relfilenode change has
- * survived into, or zero if not changed in the current transaction (or we
- * have forgotten changing it). rd_newRelfilenodeSubid can be forgotten
- * when a relation has multiple new relfilenodes within a single
- * transaction, with one of them occurring in a subsequently aborted
- * subtransaction, e.g. BEGIN; TRUNCATE t; SAVEPOINT save; TRUNCATE t;
- * ROLLBACK TO save; -- rd_newRelfilenodeSubid is now forgotten
+ * survived into or zero if the rel was not created in the current top
+ * transaction. rd_firstRelfilenodeSubid is the ID of the highest
+ * subtransaction an rd_node change has survived into or zero if rd_node
+ * matches the value it had at the start of the current top transaction.
+ * (Rolling back the subtransaction that rd_firstRelfilenodeSubid denotes
+ * would restore rd_node to the value it had at the start of the current
+ * top transaction. Rolling back any lower subtransaction would not.)
+ * Their accuracy is critical to RelationNeedsWAL().
+ *
+ * rd_newRelfilenodeSubid is the ID of the highest subtransaction the
+ * most-recent relfilenode change has survived into or zero if not changed
+ * in the current transaction (or we have forgotten changing it). This
+ * field is accurate when non-zero, but it can be zero when a relation has
+ * multiple new relfilenodes within a single transaction, with one of them
+ * occurring in a subsequently aborted subtransaction, e.g.
+ * BEGIN;
+ * TRUNCATE t;
+ * SAVEPOINT save;
+ * TRUNCATE t;
+ * ROLLBACK TO save;
+ * -- rd_newRelfilenodeSubid is now forgotten
+ *
+ * These fields are read-only outside relcache.c. Other files trigger
+ * rd_node changes by updating pg_class.reltablespace and/or
+ * pg_class.relfilenode. They must call RelationAssumeNewRelfilenode() to
+ * update these fields.
*/
SubTransactionId rd_createSubid; /* rel was created in current xact */
- SubTransactionId rd_newRelfilenodeSubid; /* new relfilenode assigned in
- * current xact */
+ SubTransactionId rd_newRelfilenodeSubid; /* highest subxact changing
+ * rd_node to current value */
+ SubTransactionId rd_firstRelfilenodeSubid; /* highest subxact changing
+ * rd_node to any value */
Form_pg_class rd_rel; /* RELATION tuple */
TupleDesc rd_att; /* tuple descriptor */
@@ -526,9 +544,16 @@ typedef struct ViewOptions
/*
* RelationNeedsWAL
* True if relation needs WAL.
- */
-#define RelationNeedsWAL(relation) \
- ((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+ *
+ * Returns false if wal_level = minimal and this relation is created or
+ * truncated in the current transaction. See "Skipping WAL for New
+ * RelFileNode" in src/backend/access/transam/README.
+ */
+#define RelationNeedsWAL(relation) \
+ ((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT && \
+ (XLogIsNeeded() || \
+ (relation->rd_createSubid == InvalidSubTransactionId && \
+ relation->rd_firstRelfilenodeSubid == InvalidSubTransactionId)))
/*
* RelationUsesLocalBuffers
diff --git a/src/include/utils/relcache.h b/src/include/utils/relcache.h
index d77f5beec6..62239a09e8 100644
--- a/src/include/utils/relcache.h
+++ b/src/include/utils/relcache.h
@@ -106,9 +106,10 @@ extern Relation RelationBuildLocalRelation(const char *relname,
char relkind);
/*
- * Routine to manage assignment of new relfilenode to a relation
+ * Routines to manage assignment of new relfilenode to a relation
*/
extern void RelationSetNewRelfilenode(Relation relation, char persistence);
+extern void RelationAssumeNewRelfilenode(Relation relation);
/*
* Routines for flushing/rebuilding relcache entries in various scenarios
@@ -121,6 +122,11 @@ extern void RelationCacheInvalidate(void);
extern void RelationCloseSmgrByOid(Oid relationId);
+#ifdef USE_ASSERT_CHECKING
+extern void AssertPendingSyncs_RelationCache(void);
+#else
+#define AssertPendingSyncs_RelationCache() do {} while (0)
+#endif
extern void AtEOXact_RelationCache(bool isCommit);
extern void AtEOSubXact_RelationCache(bool isCommit, SubTransactionId mySubid,
SubTransactionId parentSubid);
diff --git a/src/test/recovery/t/018_wal_optimize.pl b/src/test/recovery/t/018_wal_optimize.pl
new file mode 100644
index 0000000000..78d81e12d0
--- /dev/null
+++ b/src/test/recovery/t/018_wal_optimize.pl
@@ -0,0 +1,374 @@
+# Test WAL replay when some operation has skipped WAL.
+#
+# These tests exercise code that once violated the mandate described in
+# src/backend/access/transam/README section "Skipping WAL for New
+# RelFileNode". The tests work by committing some transactions, initiating an
+# immediate shutdown, and confirming that the expected data survives recovery.
+# For many years, individual commands made the decision to skip WAL, hence the
+# frequent appearance of COPY in these tests.
+use strict;
+use warnings;
+
+use PostgresNode;
+use TestLib;
+use Test::More tests => 34;
+
+sub check_orphan_relfilenodes
+{
+ my ($node, $test_name) = @_;
+
+ my $db_oid = $node->safe_psql('postgres',
+ "SELECT oid FROM pg_database WHERE datname = 'postgres'");
+ my $prefix = "base/$db_oid/";
+ my $filepaths_referenced = $node->safe_psql(
+ 'postgres', "
+ SELECT pg_relation_filepath(oid) FROM pg_class
+ WHERE reltablespace = 0 AND relpersistence <> 't' AND
+ pg_relation_filepath(oid) IS NOT NULL;");
+ is_deeply(
+ [
+ sort(map { "$prefix$_" }
+ grep(/^[0-9]+$/, slurp_dir($node->data_dir . "/$prefix")))
+ ],
+ [ sort split /\n/, $filepaths_referenced ],
+ $test_name);
+ return;
+}
+
+# We run this same test suite for both wal_level=minimal and replica.
+sub run_wal_optimize
+{
+ my $wal_level = shift;
+
+ my $node = get_new_node("node_$wal_level");
+ $node->init;
+ $node->append_conf(
+ 'postgresql.conf', qq(
+wal_level = $wal_level
+max_prepared_transactions = 1
+wal_log_hints = on
+wal_skip_threshold = 0
+#wal_debug = on
+));
+ $node->start;
+
+ # Setup
+ my $tablespace_dir = $node->basedir . '/tablespace_other';
+ mkdir($tablespace_dir);
+ $tablespace_dir = TestLib::perl2host($tablespace_dir);
+ $node->safe_psql('postgres',
+ "CREATE TABLESPACE other LOCATION '$tablespace_dir';");
+
+ # Test direct truncation optimization. No tuples.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE trunc (id serial PRIMARY KEY);
+ TRUNCATE trunc;
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ my $result = $node->safe_psql('postgres', "SELECT count(*) FROM trunc;");
+ is($result, qq(0), "wal_level = $wal_level, TRUNCATE with empty table");
+
+ # Test truncation with inserted tuples within the same transaction.
+ # Tuples inserted after the truncation should be seen.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE trunc_ins (id serial PRIMARY KEY);
+ INSERT INTO trunc_ins VALUES (DEFAULT);
+ TRUNCATE trunc_ins;
+ INSERT INTO trunc_ins VALUES (DEFAULT);
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM trunc_ins;");
+ is($result, qq(1), "wal_level = $wal_level, TRUNCATE INSERT");
+
+ # Same for prepared transaction.
+ # Tuples inserted after the truncation should be seen.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE twophase (id serial PRIMARY KEY);
+ INSERT INTO twophase VALUES (DEFAULT);
+ TRUNCATE twophase;
+ INSERT INTO twophase VALUES (DEFAULT);
+ PREPARE TRANSACTION 't';
+ COMMIT PREPARED 't';");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM twophase;");
+ is($result, qq(1), "wal_level = $wal_level, TRUNCATE INSERT PREPARE");
+
+ # Same with writing WAL at end of xact, instead of syncing.
+ # Tuples inserted after the truncation should be seen.
+ $node->safe_psql(
+ 'postgres', "
+ SET wal_skip_threshold = '1TB';
+ BEGIN;
+ CREATE TABLE noskip (id serial PRIMARY KEY);
+ INSERT INTO noskip VALUES (DEFAULT);
+ TRUNCATE noskip;
+ INSERT INTO noskip VALUES (DEFAULT);
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM noskip;");
+ is($result, qq(1),
+ "wal_level = $wal_level, TRUNCATE with end-of-xact WAL");
+
+ # Data file for COPY query in subsequent tests
+ my $basedir = $node->basedir;
+ my $copy_file = "$basedir/copy_data.txt";
+ TestLib::append_to_file(
+ $copy_file, qq(20000,30000
+20001,30001
+20002,30002));
+
+ # Test truncation with inserted tuples using both INSERT and COPY. Tuples
+ # inserted after the truncation should be seen.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE ins_trunc (id serial PRIMARY KEY, id2 int);
+ INSERT INTO ins_trunc VALUES (DEFAULT, generate_series(1,10000));
+ TRUNCATE ins_trunc;
+ INSERT INTO ins_trunc (id, id2) VALUES (DEFAULT, 10000);
+ COPY ins_trunc FROM '$copy_file' DELIMITER ',';
+ INSERT INTO ins_trunc (id, id2) VALUES (DEFAULT, 10000);
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM ins_trunc;");
+ is($result, qq(5), "wal_level = $wal_level, TRUNCATE COPY INSERT");
+
+ # Test truncation with inserted tuples using COPY. Tuples copied after
+ # the truncation should be seen.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE trunc_copy (id serial PRIMARY KEY, id2 int);
+ INSERT INTO trunc_copy VALUES (DEFAULT, generate_series(1,3000));
+ TRUNCATE trunc_copy;
+ COPY trunc_copy FROM '$copy_file' DELIMITER ',';
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result =
+ $node->safe_psql('postgres', "SELECT count(*) FROM trunc_copy;");
+ is($result, qq(3), "wal_level = $wal_level, TRUNCATE COPY");
+
+ # Like previous test, but rollback SET TABLESPACE in a subtransaction.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE spc_abort (id serial PRIMARY KEY, id2 int);
+ INSERT INTO spc_abort VALUES (DEFAULT, generate_series(1,3000));
+ TRUNCATE spc_abort;
+ SAVEPOINT s;
+ ALTER TABLE spc_abort SET TABLESPACE other; ROLLBACK TO s;
+ COPY spc_abort FROM '$copy_file' DELIMITER ',';
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM spc_abort;");
+ is($result, qq(3),
+ "wal_level = $wal_level, SET TABLESPACE abort subtransaction");
+
+ # in different subtransaction patterns
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE spc_commit (id serial PRIMARY KEY, id2 int);
+ INSERT INTO spc_commit VALUES (DEFAULT, generate_series(1,3000));
+ TRUNCATE spc_commit;
+ SAVEPOINT s; ALTER TABLE spc_commit SET TABLESPACE other; RELEASE s;
+ COPY spc_commit FROM '$copy_file' DELIMITER ',';
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result =
+ $node->safe_psql('postgres', "SELECT count(*) FROM spc_commit;");
+ is($result, qq(3),
+ "wal_level = $wal_level, SET TABLESPACE commit subtransaction");
+
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE spc_nest (id serial PRIMARY KEY, id2 int);
+ INSERT INTO spc_nest VALUES (DEFAULT, generate_series(1,3000));
+ TRUNCATE spc_nest;
+ SAVEPOINT s;
+ ALTER TABLE spc_nest SET TABLESPACE other;
+ SAVEPOINT s2;
+ ALTER TABLE spc_nest SET TABLESPACE pg_default;
+ ROLLBACK TO s2;
+ SAVEPOINT s2;
+ ALTER TABLE spc_nest SET TABLESPACE pg_default;
+ RELEASE s2;
+ ROLLBACK TO s;
+ COPY spc_nest FROM '$copy_file' DELIMITER ',';
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM spc_nest;");
+ is($result, qq(3),
+ "wal_level = $wal_level, SET TABLESPACE nested subtransaction");
+
+ $node->safe_psql(
+ 'postgres', "
+ CREATE TABLE spc_hint (id int);
+ INSERT INTO spc_hint VALUES (1);
+ BEGIN;
+ ALTER TABLE spc_hint SET TABLESPACE other;
+ CHECKPOINT;
+ SELECT * FROM spc_hint; -- set hint bit
+ INSERT INTO spc_hint VALUES (2);
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM spc_hint;");
+ is($result, qq(2), "wal_level = $wal_level, SET TABLESPACE, hint bit");
+
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE idx_hint (c int PRIMARY KEY);
+ SAVEPOINT q; INSERT INTO idx_hint VALUES (1); ROLLBACK TO q;
+ CHECKPOINT;
+ INSERT INTO idx_hint VALUES (1); -- set index hint bit
+ INSERT INTO idx_hint VALUES (2);
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->psql('postgres',);
+ my ($ret, $stdout, $stderr) =
+ $node->psql('postgres', "INSERT INTO idx_hint VALUES (2);");
+ is($ret, qq(3), "wal_level = $wal_level, unique index LP_DEAD");
+ like(
+ $stderr,
+ qr/violates unique/,
+ "wal_level = $wal_level, unique index LP_DEAD message");
+
+ # UPDATE touches two buffers for one row.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE upd (id serial PRIMARY KEY, id2 int);
+ INSERT INTO upd (id, id2) VALUES (DEFAULT, generate_series(1,10000));
+ COPY upd FROM '$copy_file' DELIMITER ',';
+ UPDATE upd SET id2 = id2 + 1;
+ DELETE FROM upd;
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM upd;");
+ is($result, qq(0),
+ "wal_level = $wal_level, UPDATE touches two buffers for one row");
+
+ # Test consistency of COPY with INSERT for table created in the same
+ # transaction.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE ins_copy (id serial PRIMARY KEY, id2 int);
+ INSERT INTO ins_copy VALUES (DEFAULT, 1);
+ COPY ins_copy FROM '$copy_file' DELIMITER ',';
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM ins_copy;");
+ is($result, qq(4), "wal_level = $wal_level, INSERT COPY");
+
+ # Test consistency of COPY that inserts more to the same table using
+ # triggers. If the INSERTS from the trigger go to the same block data
+ # is copied to, and the INSERTs are WAL-logged, WAL replay will fail when
+ # it tries to replay the WAL record but the "before" image doesn't match,
+ # because not all changes were WAL-logged.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE ins_trig (id serial PRIMARY KEY, id2 text);
+ CREATE FUNCTION ins_trig_before_row_trig() RETURNS trigger
+ LANGUAGE plpgsql as \$\$
+ BEGIN
+ IF new.id2 NOT LIKE 'triggered%' THEN
+ INSERT INTO ins_trig
+ VALUES (DEFAULT, 'triggered row before' || NEW.id2);
+ END IF;
+ RETURN NEW;
+ END; \$\$;
+ CREATE FUNCTION ins_trig_after_row_trig() RETURNS trigger
+ LANGUAGE plpgsql as \$\$
+ BEGIN
+ IF new.id2 NOT LIKE 'triggered%' THEN
+ INSERT INTO ins_trig
+ VALUES (DEFAULT, 'triggered row after' || OLD.id2);
+ END IF;
+ RETURN NEW;
+ END; \$\$;
+ CREATE TRIGGER ins_trig_before_row_insert
+ BEFORE INSERT ON ins_trig
+ FOR EACH ROW EXECUTE PROCEDURE ins_trig_before_row_trig();
+ CREATE TRIGGER ins_trig_after_row_insert
+ AFTER INSERT ON ins_trig
+ FOR EACH ROW EXECUTE PROCEDURE ins_trig_after_row_trig();
+ COPY ins_trig FROM '$copy_file' DELIMITER ',';
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result = $node->safe_psql('postgres', "SELECT count(*) FROM ins_trig;");
+ is($result, qq(9), "wal_level = $wal_level, COPY with INSERT triggers");
+
+ # Test consistency of INSERT, COPY and TRUNCATE in same transaction block
+ # with TRUNCATE triggers.
+ $node->safe_psql(
+ 'postgres', "
+ BEGIN;
+ CREATE TABLE trunc_trig (id serial PRIMARY KEY, id2 text);
+ CREATE FUNCTION trunc_trig_before_stat_trig() RETURNS trigger
+ LANGUAGE plpgsql as \$\$
+ BEGIN
+ INSERT INTO trunc_trig VALUES (DEFAULT, 'triggered stat before');
+ RETURN NULL;
+ END; \$\$;
+ CREATE FUNCTION trunc_trig_after_stat_trig() RETURNS trigger
+ LANGUAGE plpgsql as \$\$
+ BEGIN
+ INSERT INTO trunc_trig VALUES (DEFAULT, 'triggered stat before');
+ RETURN NULL;
+ END; \$\$;
+ CREATE TRIGGER trunc_trig_before_stat_truncate
+ BEFORE TRUNCATE ON trunc_trig
+ FOR EACH STATEMENT EXECUTE PROCEDURE trunc_trig_before_stat_trig();
+ CREATE TRIGGER trunc_trig_after_stat_truncate
+ AFTER TRUNCATE ON trunc_trig
+ FOR EACH STATEMENT EXECUTE PROCEDURE trunc_trig_after_stat_trig();
+ INSERT INTO trunc_trig VALUES (DEFAULT, 1);
+ TRUNCATE trunc_trig;
+ COPY trunc_trig FROM '$copy_file' DELIMITER ',';
+ COMMIT;");
+ $node->stop('immediate');
+ $node->start;
+ $result =
+ $node->safe_psql('postgres', "SELECT count(*) FROM trunc_trig;");
+ is($result, qq(4),
+ "wal_level = $wal_level, TRUNCATE COPY with TRUNCATE triggers");
+
+ # Test redo of temp table creation.
+ $node->safe_psql(
+ 'postgres', "
+ CREATE TEMP TABLE temp (id serial PRIMARY KEY, id2 text);");
+ $node->stop('immediate');
+ $node->start;
+ check_orphan_relfilenodes($node,
+ "wal_level = $wal_level, no orphan relfilenode remains");
+
+ return;
+}
+
+# Run same test suite for multiple wal_level values.
+run_wal_optimize("minimal");
+run_wal_optimize("replica");
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 4dd3507c99..57767bab6d 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -1984,6 +1984,12 @@ select * from another;
(3 rows)
drop table another;
+-- Create an index that skips WAL, then perform a SET DATA TYPE that skips
+-- rewriting the index.
+begin;
+create table skip_wal_skip_rewrite_index (c varchar(10) primary key);
+alter table skip_wal_skip_rewrite_index alter c type varchar(20);
+commit;
-- table's row type
create table tab1 (a int, b text);
create table tab2 (x int, y tab1);
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index a16e4c9a29..e11399f2cd 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -1360,6 +1360,13 @@ select * from another;
drop table another;
+-- Create an index that skips WAL, then perform a SET DATA TYPE that skips
+-- rewriting the index.
+begin;
+create table skip_wal_skip_rewrite_index (c varchar(10) primary key);
+alter table skip_wal_skip_rewrite_index alter c type varchar(20);
+commit;
+
-- table's row type
create table tab1 (a int, b text);
create table tab2 (x int, y tab1);
--
2.23.0
From 11e6a21ddbc847128e204dac6ba0f62734dd141c Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Date: Tue, 14 Jan 2020 19:24:04 +0900
Subject: [PATCH v33 2/4] Fix the defect 1
Pending sync is lost by the followig sequence.
begin;
create table t (c int);
savepoint q; drop table t; rollback to q; -- forgets table is skipping wal
commit; -- assertion failure
Relcache entry for a dropped relation is deleted right out. On the
other hand we need the newness information holded in the dropped entry
if the subtransaction is rolled back later. So this patch makes
relcache entry preserved after dropping of a relation that any newness
flag is active, so that it is available later in the current
transaction.
---
src/backend/utils/cache/relcache.c | 138 ++++++++++++++++++++++++++---
src/include/utils/rel.h | 2 +
src/include/utils/relcache.h | 1 +
3 files changed, 131 insertions(+), 10 deletions(-)
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 0ac72572e3..a223cc0f94 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -18,6 +18,7 @@
* RelationCacheInitializePhase2 - initialize shared-catalog entries
* RelationCacheInitializePhase3 - finish initializing relcache
* RelationIdGetRelation - get a reldesc by relation id
+ * RelationIdGetRelationCache - get a relcache entry by relation id
* RelationClose - close an open relation
*
* NOTES
@@ -1094,6 +1095,7 @@ RelationBuildDesc(Oid targetRelId, bool insertIt)
relation->rd_createSubid = InvalidSubTransactionId;
relation->rd_newRelfilenodeSubid = InvalidSubTransactionId;
relation->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
+ relation->rd_droppedSubid = InvalidSubTransactionId;
switch (relation->rd_rel->relpersistence)
{
case RELPERSISTENCE_UNLOGGED:
@@ -1991,6 +1993,13 @@ RelationIdGetRelation(Oid relationId)
if (RelationIsValid(rd))
{
+ /* return NULL for dropped relatoins */
+ if (rd->rd_droppedSubid != InvalidSubTransactionId)
+ {
+ Assert (!rd->rd_isvalid);
+ return NULL;
+ }
+
RelationIncrementReferenceCount(rd);
/* revalidate cache entry if necessary */
if (!rd->rd_isvalid)
@@ -2030,6 +2039,31 @@ RelationIdGetRelation(Oid relationId)
return rd;
}
+/*
+ * RelationIdGetRelationCache: returns an entry exists in relcache.
+ *
+ * This function returns NULL not building new one if no existing entries
+ * found, and may return an invalid or dropped-but-not-commited entry if any.
+ *
+ * This function is intended to be used to lookup the relcache entriy for a
+ * relation that have been created then dropped in the current transaction.
+ */
+Relation
+RelationIdGetRelationCache(Oid relationId)
+{
+ Relation rd;
+
+ /* Make sure we're in an xact, even if this ends up being a cache hit */
+ Assert(IsTransactionState());
+
+ RelationIdCacheLookup(relationId, rd);
+
+ if (RelationIsValid(rd))
+ RelationIncrementReferenceCount(rd);
+
+ return rd;
+}
+
/* ----------------------------------------------------------------
* cache invalidation support routines
* ----------------------------------------------------------------
@@ -2134,10 +2168,11 @@ RelationReloadIndexInfo(Relation relation)
HeapTuple pg_class_tuple;
Form_pg_class relp;
- /* Should be called only for invalidated indexes */
+ /* Should be called only for invalidated living indexes */
Assert((relation->rd_rel->relkind == RELKIND_INDEX ||
relation->rd_rel->relkind == RELKIND_PARTITIONED_INDEX) &&
- !relation->rd_isvalid);
+ !relation->rd_isvalid &&
+ relation->rd_droppedSubid == InvalidSubTransactionId);
/* Ensure it's closed at smgr level */
RelationCloseSmgr(relation);
@@ -2443,7 +2478,8 @@ RelationClearRelation(Relation relation, bool rebuild)
if ((relation->rd_rel->relkind == RELKIND_INDEX ||
relation->rd_rel->relkind == RELKIND_PARTITIONED_INDEX) &&
relation->rd_refcnt > 0 &&
- relation->rd_indexcxt != NULL)
+ relation->rd_indexcxt != NULL &&
+ relation->rd_droppedSubid == InvalidSubTransactionId)
{
relation->rd_isvalid = false; /* needs to be revalidated */
if (IsTransactionState())
@@ -2462,6 +2498,25 @@ RelationClearRelation(Relation relation, bool rebuild)
*/
if (!rebuild)
{
+ /*
+ * The relcache entry is still needed to perform at-commit sync if the
+ * subtransaction aborts later. Mark the relcache as "dropped" and
+ * leave it live invalid.
+ */
+ if (relation->rd_createSubid != InvalidSubTransactionId)
+ {
+ if (relation->rd_droppedSubid == InvalidSubTransactionId)
+ relation->rd_droppedSubid = GetCurrentSubTransactionId();
+ else
+ {
+ /* shouldn't try to update it */
+ Assert (relation->rd_droppedSubid ==
+ GetCurrentSubTransactionId());
+ }
+
+ return;
+ }
+
/* Remove it from the hash table */
RelationCacheDelete(relation);
@@ -2546,6 +2601,26 @@ RelationClearRelation(Relation relation, bool rebuild)
if (HistoricSnapshotActive())
return;
+ /*
+ * Although this relation is already dropped from catalog, the
+ * relcache entry is still needed to perform at-commit sync if the
+ * subtransaction aborts later. Mark the relcache as "dropped" and
+ * leave it live invalid.
+ */
+ if (relation->rd_createSubid != InvalidSubTransactionId)
+ {
+ if (relation->rd_droppedSubid == InvalidSubTransactionId)
+ relation->rd_droppedSubid = GetCurrentSubTransactionId();
+ else
+ {
+ /* shouldn't try to update it */
+ Assert (relation->rd_droppedSubid ==
+ GetCurrentSubTransactionId());
+ }
+
+ return;
+ }
+
/*
* This shouldn't happen as dropping a relation is intended to be
* impossible if still referenced (cf. CheckTableNotInUse()). But
@@ -2598,6 +2673,7 @@ RelationClearRelation(Relation relation, bool rebuild)
SWAPFIELD(SubTransactionId, rd_createSubid);
SWAPFIELD(SubTransactionId, rd_newRelfilenodeSubid);
SWAPFIELD(SubTransactionId, rd_firstRelfilenodeSubid);
+ SWAPFIELD(SubTransactionId, rd_droppedSubid);
/* un-swap rd_rel pointers, swap contents instead */
SWAPFIELD(Form_pg_class, rd_rel);
/* ... but actually, we don't have to update newrel->rd_rel */
@@ -2978,8 +3054,8 @@ AssertPendingSyncs_RelationCache(void)
LOCKTAG_RELATION)
continue;
relid = ObjectIdGetDatum(locallock->tag.lock.locktag_field2);
- r = RelationIdGetRelation(relid);
- if (r == NULL)
+ r = RelationIdGetRelationCache(relid);
+ if (!RelationIsValid(r))
continue;
if (nrels >= maxrels)
{
@@ -2991,7 +3067,20 @@ AssertPendingSyncs_RelationCache(void)
hash_seq_init(&status, RelationIdCache);
while ((idhentry = (RelIdCacheEnt *) hash_seq_search(&status)) != NULL)
- AssertPendingSyncConsistency(idhentry->reldesc);
+ {
+ Relation r = idhentry->reldesc;
+
+ /* Ignore relcache entries of deleted relations */
+ if (r->rd_droppedSubid != InvalidSubTransactionId)
+ {
+ Assert(!r->rd_isvalid &&
+ (r->rd_createSubid != InvalidSubTransactionId ||
+ r->rd_firstRelfilenodeSubid != InvalidSubTransactionId));
+ continue;
+ }
+
+ AssertPendingSyncConsistency(r);
+ }
for (i = 0; i < nrels; i++)
RelationClose(rels[i]);
@@ -3114,8 +3203,23 @@ AtEOXact_cleanup(Relation relation, bool isCommit)
*/
if (relation->rd_createSubid != InvalidSubTransactionId)
{
- if (isCommit)
- relation->rd_createSubid = InvalidSubTransactionId;
+ /* dropped subid must be the same with carete subid if any */
+ Assert (relation->rd_droppedSubid == InvalidSubTransactionId ||
+ relation->rd_createSubid == relation->rd_droppedSubid);
+
+ /*
+ * cancel rd_createSubid to let RelationClearRelation drop the relcache
+ * entry.
+ */
+ relation->rd_createSubid = InvalidSubTransactionId;
+
+ /*
+ * Besides at rollback, if we have dropped an in-transaction-created
+ * relation, the corresponding relcache entry is preserved for pending
+ * sync. We must remove such entries at commit.
+ */
+ if (isCommit && relation->rd_droppedSubid == InvalidSubTransactionId)
+ {} /* Nothing to do*/
else if (RelationHasReferenceCountZero(relation))
{
RelationClearRelation(relation, false);
@@ -3131,7 +3235,6 @@ AtEOXact_cleanup(Relation relation, bool isCommit)
* eventually. This must be just a WARNING to avoid
* error-during-error-recovery loops.
*/
- relation->rd_createSubid = InvalidSubTransactionId;
elog(WARNING, "cannot remove relcache entry for \"%s\" because it has nonzero refcount",
RelationGetRelationName(relation));
}
@@ -3210,7 +3313,7 @@ AtEOSubXact_cleanup(Relation relation, bool isCommit,
*/
if (relation->rd_createSubid == mySubid)
{
- if (isCommit)
+ if (isCommit && relation->rd_droppedSubid != mySubid)
relation->rd_createSubid = parentSubid;
else if (RelationHasReferenceCountZero(relation))
{
@@ -3232,6 +3335,21 @@ AtEOSubXact_cleanup(Relation relation, bool isCommit,
}
}
+ /*
+ * Is it a relation create then dropped in the current subtransaction?
+ *
+ * If this relation registered pending sync then dropped, subxact rollback
+ * cancels the uncommitted drop, and commit propagates it to the parent.
+ */
+ if (relation->rd_droppedSubid == mySubid)
+ {
+ if (isCommit)
+ relation->rd_droppedSubid = parentSubid;
+ else
+ relation->rd_droppedSubid = InvalidSubTransactionId;
+ }
+
+
/*
* Likewise, update or drop any new-relfilenode-in-subtransaction record.
*/
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index ad72a8b910..0b87bc3222 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -98,6 +98,8 @@ typedef struct RelationData
* rd_node to current value */
SubTransactionId rd_firstRelfilenodeSubid; /* highest subxact changing
* rd_node to any value */
+ SubTransactionId rd_droppedSubid; /* in-transaction created rel has been
+ * dropped */
Form_pg_class rd_rel; /* RELATION tuple */
TupleDesc rd_att; /* tuple descriptor */
diff --git a/src/include/utils/relcache.h b/src/include/utils/relcache.h
index 62239a09e8..0362b6f6ff 100644
--- a/src/include/utils/relcache.h
+++ b/src/include/utils/relcache.h
@@ -37,6 +37,7 @@ typedef Relation *RelationPtr;
* Routines to open (lookup) and close a relcache entry
*/
extern Relation RelationIdGetRelation(Oid relationId);
+extern Relation RelationIdGetRelationCache(Oid relationId);
extern void RelationClose(Relation relation);
/*
--
2.23.0
From f631de03776f79b0d47ce49c34b221310616b448 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Date: Tue, 21 Jan 2020 18:12:52 +0900
Subject: [PATCH v33 3/4] Fix the defect 2
Pass newness flags to new index relation inherits the old relfilenode
whie ALTER TABLE ALTER TYPE.
The command may reuse existing index and the reused index may be
created in the current transaction. Pass the information to the
relcache of the new index relation so that pending sync correctly
works. This relies on the relcache preserving feature introduced by
the previos fix.
---
src/backend/commands/tablecmds.c | 32 +++++++++++++++++++++++++++++---
src/backend/nodes/copyfuncs.c | 1 +
src/backend/nodes/equalfuncs.c | 1 +
src/backend/nodes/outfuncs.c | 1 +
src/include/nodes/parsenodes.h | 1 +
5 files changed, 33 insertions(+), 3 deletions(-)
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 1b8e38d3aa..c84ba293d4 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -7676,12 +7676,35 @@ ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
* this index will have scheduled the storage for deletion at commit, so
* cancel that pending deletion.
*/
+ Assert (OidIsValid(stmt->oldNode) == OidIsValid(stmt->oldRelId));
if (OidIsValid(stmt->oldNode))
{
- Relation irel = index_open(address.objectId, NoLock);
+ Relation newirel = index_open(address.objectId, NoLock);
+ Relation oldirel = RelationIdGetRelationCache(stmt->oldRelId);
- RelationPreserveStorage(irel->rd_node, true);
- index_close(irel, NoLock);
+ RelationPreserveStorage(newirel->rd_node, true);
+
+ /*
+ * oidirel is valid iff the old relation was created then dropped in
+ * the current transaction. We need to copy the newness hints other
+ * than rd_droppedSubid corresponding to the reused relfilenode in that
+ * case.
+ */
+ if (oldirel != NULL)
+ {
+ Assert(!oldirel->rd_isvalid &&
+ oldirel->rd_createSubid != InvalidSubTransactionId &&
+ oldirel->rd_droppedSubid != InvalidSubTransactionId);
+
+ newirel->rd_createSubid = oldirel->rd_createSubid;
+ newirel->rd_firstRelfilenodeSubid =
+ oldirel->rd_firstRelfilenodeSubid;
+ newirel->rd_newRelfilenodeSubid =
+ oldirel->rd_newRelfilenodeSubid;
+
+ RelationClose(oldirel);
+ }
+ index_close(newirel, NoLock);
}
return address;
@@ -11960,7 +11983,10 @@ TryReuseIndex(Oid oldId, IndexStmt *stmt)
/* If it's a partitioned index, there is no storage to share. */
if (irel->rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
+ {
stmt->oldNode = irel->rd_node.relNode;
+ stmt->oldRelId = irel->rd_id;
+ }
index_close(irel, NoLock);
}
}
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 54ad62bb7f..0e621d74d4 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -3477,6 +3477,7 @@ _copyIndexStmt(const IndexStmt *from)
COPY_STRING_FIELD(idxcomment);
COPY_SCALAR_FIELD(indexOid);
COPY_SCALAR_FIELD(oldNode);
+ COPY_SCALAR_FIELD(oldRelId);
COPY_SCALAR_FIELD(unique);
COPY_SCALAR_FIELD(primary);
COPY_SCALAR_FIELD(isconstraint);
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index 5b1ba143b1..5740b6890b 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -1345,6 +1345,7 @@ _equalIndexStmt(const IndexStmt *a, const IndexStmt *b)
COMPARE_STRING_FIELD(idxcomment);
COMPARE_SCALAR_FIELD(indexOid);
COMPARE_SCALAR_FIELD(oldNode);
+ COMPARE_SCALAR_FIELD(oldRelId);
COMPARE_SCALAR_FIELD(unique);
COMPARE_SCALAR_FIELD(primary);
COMPARE_SCALAR_FIELD(isconstraint);
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index d76fae44b8..bcbdb29ccb 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -2650,6 +2650,7 @@ _outIndexStmt(StringInfo str, const IndexStmt *node)
WRITE_STRING_FIELD(idxcomment);
WRITE_OID_FIELD(indexOid);
WRITE_OID_FIELD(oldNode);
+ WRITE_OID_FIELD(oldRelId);
WRITE_BOOL_FIELD(unique);
WRITE_BOOL_FIELD(primary);
WRITE_BOOL_FIELD(isconstraint);
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index da0706add5..b114d7a772 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2782,6 +2782,7 @@ typedef struct IndexStmt
char *idxcomment; /* comment to apply to index, or NULL */
Oid indexOid; /* OID of an existing index, if any */
Oid oldNode; /* relfilenode of existing storage, if any */
+ Oid oldRelId; /* relid of the old index, if any */
bool unique; /* is index unique? */
bool primary; /* is index a primary key? */
bool isconstraint; /* is it for a pkey/unique constraint? */
--
2.23.0
From fb3ef683bcce318b65b91ddce4e1740224c08d59 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Date: Thu, 16 Jan 2020 13:24:27 +0900
Subject: [PATCH v33 4/4] Fix the defect 3
Force file sync if the file has been truncated.
The previous verision of the patch allowed to choose WAL when main
fork is larger than ever. But there's a case where FSM fork gets
shorter while main fork is larger than ever. Force file sync always
when the file has experienced a truncation.
---
src/backend/catalog/storage.c | 56 +++++++++++++++++++----------------
1 file changed, 31 insertions(+), 25 deletions(-)
diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c
index 8253c420ef..447fb606e5 100644
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@@ -68,7 +68,7 @@ typedef struct PendingRelDelete
typedef struct pendingSync
{
RelFileNode rnode;
- BlockNumber max_truncated;
+ bool is_truncated; /* Has the file experienced truncation? */
} pendingSync;
static PendingRelDelete *pendingDeletes = NULL; /* head of linked list */
@@ -154,7 +154,7 @@ RelationCreateStorage(RelFileNode rnode, char relpersistence)
pending = hash_search(pendingSyncHash, &rnode, HASH_ENTER, &found);
Assert(!found);
- pending->max_truncated = 0;
+ pending->is_truncated = false;
}
return srel;
@@ -388,13 +388,7 @@ RelationPreTruncate(Relation rel)
/* Record largest maybe-unsynced block of files under tracking */
pending = hash_search(pendingSyncHash, &(rel->rd_smgr->smgr_rnode.node),
HASH_FIND, NULL);
- if (pending)
- {
- BlockNumber nblocks = smgrnblocks(rel->rd_smgr, MAIN_FORKNUM);
-
- if (pending->max_truncated < nblocks)
- pending->max_truncated = nblocks;
- }
+ pending->is_truncated = true;
}
/*
@@ -637,31 +631,43 @@ smgrDoPendingSyncs(bool isCommit)
* Small WAL records have a chance to be emitted along with other
* backends' WAL records. We emit WAL records instead of syncing for
* files that are smaller than a certain threshold, expecting faster
- * commit. The threshold is defined by the GUC wal_skip_threshold.
+ * commit. The threshold is defined by the GUC wal_skip_threshold. We
+ * don't bother counting the pages when the file has experienced a
+ * truncation.
*/
- for (fork = 0; fork <= MAX_FORKNUM; fork++)
+ if (!pendingsync->is_truncated)
{
- if (smgrexists(srel, fork))
+ for (fork = 0; fork <= MAX_FORKNUM; fork++)
{
- BlockNumber n = smgrnblocks(srel, fork);
-
- /* we shouldn't come here for unlogged relations */
- Assert(fork != INIT_FORKNUM);
+ if (smgrexists(srel, fork))
+ {
+ BlockNumber n = smgrnblocks(srel, fork);
- nblocks[fork] = n;
- total_blocks += n;
+ /* we shouldn't come here for unlogged relations */
+ Assert(fork != INIT_FORKNUM);
+ nblocks[fork] = n;
+ total_blocks += n;
+ }
+ else
+ nblocks[fork] = InvalidBlockNumber;
}
- else
- nblocks[fork] = InvalidBlockNumber;
}
/*
- * Sync file or emit WAL records for its contents. Do file sync if
- * the size is larger than the threshold or truncates may have removed
- * blocks beyond the current size.
+ * Sync file or emit WAL records for its contents.
+ *
+ * Alghough we emit WAL record if the file is small enough, do file
+ * sync regardless of the size if the file has experienced a
+ * truncation. It is because the file would be followed by trailing
+ * garbage blocks after a crash recovery if, while a past longer file
+ * had been flushed out, we omitted syncing-out of the file and emit
+ * WAL instead. You might think that we could choose WAL if the
+ * current main fork is longer than ever, but there's a case where main
+ * fork is longer than ever but FSM fork gets shorter. We don't bother
+ * checking that for every fork.
*/
- if (total_blocks * BLCKSZ / 1024 >= wal_skip_threshold ||
- nblocks[MAIN_FORKNUM] < pendingsync->max_truncated)
+ if (pendingsync->is_truncated ||
+ total_blocks * BLCKSZ / 1024 >= wal_skip_threshold)
{
/* allocate the initial array, or extend it, if needed */
if (maxrels == 0)
--
2.23.0
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