Re: [HACKERS] asynchronous execution - Mailing list pgsql-hackers
| From | Kyotaro HORIGUCHI |
|---|---|
| Subject | Re: [HACKERS] asynchronous execution |
| Date | |
| Msg-id | 20180511.174520.188681124.horiguchi.kyotaro@lab.ntt.co.jp Whole thread Raw |
| In response to | Re: [HACKERS] asynchronous execution (Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>) |
| Responses |
Re: [HACKERS] asynchronous execution
(Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>)
|
| List | pgsql-hackers |
Hello. This is the new version of $Subject.
But, this is not just a rebased version. On the way fixing
serious conflicts, I refactored patch and I believe this becomes
way readable than the previous shape.
# 0003 lacks changes of postgres_fdw.out now.
- Waiting queue manipulation is moved into new functions. It had
a bug that the same node can be inserted in the queue more than
once and it is fixed.
- postgresIterateForeginScan had somewhat a tricky strcuture to
merge similar procedures thus it cannot be said easy-to-read at
all. Now it is far simpler and straight-forward looking.
- Still this works only on Append/ForeignScan.
> > The attached PoC patch theoretically has no impact on the normal
> > code paths and just brings gain in async cases.
I performed almost the same test as before but with:
- partition tables
(There should be no difference with inheritance.)
- added test for fetch_size of 200 and 1000 as long as 100.
100 unreasonably magnifies the lag by context switching on
single poor box and the test D/F below. (They became faster by
about twice by adding a small delay (1000 times of
clock_gettime()(*1)) just before epoll_wait so that it doesn't
sleep (I suppose)...)
- Table size of test B is one tenth of the previous size, the
same to one partition.
*1: The reason for the function is that first I found that the
queries get way faster by just prefixing by "explain analyze"..
> patched(ms) unpatched(ms) gain(%)
> A: simple table scan : 3562.32 3444.81 -3.4
> B: local partitioning : 1451.25 1604.38 9.5
> C: single remote table : 8818.92 9297.76 5.1
> D: sharding (single con) : 5966.14 6646.73 10.2
> E: sharding (multi con) : 1802.25 6515.49 72.3
fetch_size = 100
patched(ms) unpatched(ms) gain(%)
A: simple table scan : 3033.48 2997.44 -1.2
B: local partitioning : 1405.52 1426.66 1.5
C: single remote table : 8335.50 8463.22 1.5
D: sharding (single con) : 6862.92 6820.97 -0.6
E: sharding (multi con) : 2185.84 6733.63 67.5
F: partition (single con): 6818.13 6741.01 -1.1
G: partition (multi con) : 2150.58 6407.46 66.4
fetch_size = 200
patched(ms) unpatched(ms) gain(%)
A: simple table scan :
B: local partitioning :
C: single remote table :
D: sharding (single con) :
E: sharding (multi con) :
F: partition (single con):
G: partition (multi con) :
fetch_size = 1000
patched(ms) unpatched(ms) gain(%)
A: simple table scan : 3050.31 2980.29 -2.3
B: local partitioning : 1401.34 1419.54 1.3
C: single remote table : 8375.4 8445.27 0.8
D: sharding (single con) : 3935.97 4737.84 16.9
E: sharding (multi con) : 1330.44 4752.87 72.0
F: partition (single con): 3997.63 4747.44 15.8
G: partition (multi con) : 1323.02 4807.72 72.5
Async append doesn't affect non-async path at all so B is
expected to get no degradation. It seems within error.
C and F are the gain when all foreign tables share one connection
and D and G are the gain when every foreign tables has dedicate
connection.
I will repost after filling the blank portion of the tables and
complete regression of the patch next week. Sorry for the
incomplete post.
regards.
--
Kyotaro Horiguchi
NTT Open Source Software Center
From 7ad4210dd20b6672367255492e2b1d95cd90b122 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Mon, 22 May 2017 12:42:58 +0900
Subject: [PATCH 1/3] Allow wait event set to be registered to resource owner
WaitEventSet needs to be released using resource owner for a certain
case. This change adds WaitEventSet reowner and allow the creator of a
WaitEventSet to specify a resource owner.
---
src/backend/libpq/pqcomm.c | 2 +-
src/backend/storage/ipc/latch.c | 18 ++++++-
src/backend/storage/lmgr/condition_variable.c | 2 +-
src/backend/utils/resowner/resowner.c | 67 +++++++++++++++++++++++++++
src/include/storage/latch.h | 4 +-
src/include/utils/resowner_private.h | 8 ++++
6 files changed, 96 insertions(+), 5 deletions(-)
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index a4f6d4deeb..890972b9b8 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -220,7 +220,7 @@ pq_init(void)
(errmsg("could not set socket to nonblocking mode: %m")));
#endif
- FeBeWaitSet = CreateWaitEventSet(TopMemoryContext, 3);
+ FeBeWaitSet = CreateWaitEventSet(TopMemoryContext, NULL, 3);
AddWaitEventToSet(FeBeWaitSet, WL_SOCKET_WRITEABLE, MyProcPort->sock,
NULL, NULL);
AddWaitEventToSet(FeBeWaitSet, WL_LATCH_SET, -1, MyLatch, NULL);
diff --git a/src/backend/storage/ipc/latch.c b/src/backend/storage/ipc/latch.c
index e6706f7fb8..5457899f2d 100644
--- a/src/backend/storage/ipc/latch.c
+++ b/src/backend/storage/ipc/latch.c
@@ -51,6 +51,7 @@
#include "storage/latch.h"
#include "storage/pmsignal.h"
#include "storage/shmem.h"
+#include "utils/resowner_private.h"
/*
* Select the fd readiness primitive to use. Normally the "most modern"
@@ -77,6 +78,8 @@ struct WaitEventSet
int nevents; /* number of registered events */
int nevents_space; /* maximum number of events in this set */
+ ResourceOwner resowner; /* Resource owner */
+
/*
* Array, of nevents_space length, storing the definition of events this
* set is waiting for.
@@ -359,7 +362,7 @@ WaitLatchOrSocket(volatile Latch *latch, int wakeEvents, pgsocket sock,
int ret = 0;
int rc;
WaitEvent event;
- WaitEventSet *set = CreateWaitEventSet(CurrentMemoryContext, 3);
+ WaitEventSet *set = CreateWaitEventSet(CurrentMemoryContext, NULL, 3);
if (wakeEvents & WL_TIMEOUT)
Assert(timeout >= 0);
@@ -517,12 +520,15 @@ ResetLatch(volatile Latch *latch)
* WaitEventSetWait().
*/
WaitEventSet *
-CreateWaitEventSet(MemoryContext context, int nevents)
+CreateWaitEventSet(MemoryContext context, ResourceOwner res, int nevents)
{
WaitEventSet *set;
char *data;
Size sz = 0;
+ if (res)
+ ResourceOwnerEnlargeWESs(res);
+
/*
* Use MAXALIGN size/alignment to guarantee that later uses of memory are
* aligned correctly. E.g. epoll_event might need 8 byte alignment on some
@@ -591,6 +597,11 @@ CreateWaitEventSet(MemoryContext context, int nevents)
StaticAssertStmt(WSA_INVALID_EVENT == NULL, "");
#endif
+ /* Register this wait event set if requested */
+ set->resowner = res;
+ if (res)
+ ResourceOwnerRememberWES(set->resowner, set);
+
return set;
}
@@ -632,6 +643,9 @@ FreeWaitEventSet(WaitEventSet *set)
}
#endif
+ if (set->resowner != NULL)
+ ResourceOwnerForgetWES(set->resowner, set);
+
pfree(set);
}
diff --git a/src/backend/storage/lmgr/condition_variable.c b/src/backend/storage/lmgr/condition_variable.c
index ef1d5baf01..30edc8e83a 100644
--- a/src/backend/storage/lmgr/condition_variable.c
+++ b/src/backend/storage/lmgr/condition_variable.c
@@ -69,7 +69,7 @@ ConditionVariablePrepareToSleep(ConditionVariable *cv)
{
WaitEventSet *new_event_set;
- new_event_set = CreateWaitEventSet(TopMemoryContext, 2);
+ new_event_set = CreateWaitEventSet(TopMemoryContext, NULL, 2);
AddWaitEventToSet(new_event_set, WL_LATCH_SET, PGINVALID_SOCKET,
MyLatch, NULL);
AddWaitEventToSet(new_event_set, WL_POSTMASTER_DEATH, PGINVALID_SOCKET,
diff --git a/src/backend/utils/resowner/resowner.c b/src/backend/utils/resowner/resowner.c
index bce021e100..802b79a660 100644
--- a/src/backend/utils/resowner/resowner.c
+++ b/src/backend/utils/resowner/resowner.c
@@ -126,6 +126,7 @@ typedef struct ResourceOwnerData
ResourceArray filearr; /* open temporary files */
ResourceArray dsmarr; /* dynamic shmem segments */
ResourceArray jitarr; /* JIT contexts */
+ ResourceArray wesarr; /* wait event sets */
/* We can remember up to MAX_RESOWNER_LOCKS references to local locks. */
int nlocks; /* number of owned locks */
@@ -171,6 +172,7 @@ static void PrintTupleDescLeakWarning(TupleDesc tupdesc);
static void PrintSnapshotLeakWarning(Snapshot snapshot);
static void PrintFileLeakWarning(File file);
static void PrintDSMLeakWarning(dsm_segment *seg);
+static void PrintWESLeakWarning(WaitEventSet *events);
/*****************************************************************************
@@ -440,6 +442,7 @@ ResourceOwnerCreate(ResourceOwner parent, const char *name)
ResourceArrayInit(&(owner->filearr), FileGetDatum(-1));
ResourceArrayInit(&(owner->dsmarr), PointerGetDatum(NULL));
ResourceArrayInit(&(owner->jitarr), PointerGetDatum(NULL));
+ ResourceArrayInit(&(owner->wesarr), PointerGetDatum(NULL));
return owner;
}
@@ -549,6 +552,16 @@ ResourceOwnerReleaseInternal(ResourceOwner owner,
jit_release_context(context);
}
+
+ /* Ditto for wait event sets */
+ while (ResourceArrayGetAny(&(owner->wesarr), &foundres))
+ {
+ WaitEventSet *event = (WaitEventSet *) DatumGetPointer(foundres);
+
+ if (isCommit)
+ PrintWESLeakWarning(event);
+ FreeWaitEventSet(event);
+ }
}
else if (phase == RESOURCE_RELEASE_LOCKS)
{
@@ -697,6 +710,7 @@ ResourceOwnerDelete(ResourceOwner owner)
Assert(owner->filearr.nitems == 0);
Assert(owner->dsmarr.nitems == 0);
Assert(owner->jitarr.nitems == 0);
+ Assert(owner->wesarr.nitems == 0);
Assert(owner->nlocks == 0 || owner->nlocks == MAX_RESOWNER_LOCKS + 1);
/*
@@ -724,6 +738,7 @@ ResourceOwnerDelete(ResourceOwner owner)
ResourceArrayFree(&(owner->filearr));
ResourceArrayFree(&(owner->dsmarr));
ResourceArrayFree(&(owner->jitarr));
+ ResourceArrayFree(&(owner->wesarr));
pfree(owner);
}
@@ -1301,3 +1316,55 @@ ResourceOwnerForgetJIT(ResourceOwner owner, Datum handle)
elog(ERROR, "JIT context %p is not owned by resource owner %s",
DatumGetPointer(handle), owner->name);
}
+
+/*
+ * wait event set reference array.
+ *
+ * This is separate from actually inserting an entry because if we run out
+ * of memory, it's critical to do so *before* acquiring the resource.
+ */
+void
+ResourceOwnerEnlargeWESs(ResourceOwner owner)
+{
+ ResourceArrayEnlarge(&(owner->wesarr));
+}
+
+/*
+ * Remember that a wait event set is owned by a ResourceOwner
+ *
+ * Caller must have previously done ResourceOwnerEnlargeWESs()
+ */
+void
+ResourceOwnerRememberWES(ResourceOwner owner, WaitEventSet *events)
+{
+ ResourceArrayAdd(&(owner->wesarr), PointerGetDatum(events));
+}
+
+/*
+ * Forget that a wait event set is owned by a ResourceOwner
+ */
+void
+ResourceOwnerForgetWES(ResourceOwner owner, WaitEventSet *events)
+{
+ /*
+ * XXXX: There's no property to show as an identier of a wait event set,
+ * use its pointer instead.
+ */
+ if (!ResourceArrayRemove(&(owner->wesarr), PointerGetDatum(events)))
+ elog(ERROR, "wait event set %p is not owned by resource owner %s",
+ events, owner->name);
+}
+
+/*
+ * Debugging subroutine
+ */
+static void
+PrintWESLeakWarning(WaitEventSet *events)
+{
+ /*
+ * XXXX: There's no property to show as an identier of a wait event set,
+ * use its pointer instead.
+ */
+ elog(WARNING, "wait event set leak: %p still referenced",
+ events);
+}
diff --git a/src/include/storage/latch.h b/src/include/storage/latch.h
index a4bcb48874..838845af01 100644
--- a/src/include/storage/latch.h
+++ b/src/include/storage/latch.h
@@ -101,6 +101,7 @@
#define LATCH_H
#include <signal.h>
+#include "utils/resowner.h"
/*
* Latch structure should be treated as opaque and only accessed through
@@ -162,7 +163,8 @@ extern void DisownLatch(volatile Latch *latch);
extern void SetLatch(volatile Latch *latch);
extern void ResetLatch(volatile Latch *latch);
-extern WaitEventSet *CreateWaitEventSet(MemoryContext context, int nevents);
+extern WaitEventSet *CreateWaitEventSet(MemoryContext context,
+ ResourceOwner res, int nevents);
extern void FreeWaitEventSet(WaitEventSet *set);
extern int AddWaitEventToSet(WaitEventSet *set, uint32 events, pgsocket fd,
Latch *latch, void *user_data);
diff --git a/src/include/utils/resowner_private.h b/src/include/utils/resowner_private.h
index a6e8eb71ab..3c06e4c3f8 100644
--- a/src/include/utils/resowner_private.h
+++ b/src/include/utils/resowner_private.h
@@ -18,6 +18,7 @@
#include "storage/dsm.h"
#include "storage/fd.h"
+#include "storage/latch.h"
#include "storage/lock.h"
#include "utils/catcache.h"
#include "utils/plancache.h"
@@ -95,4 +96,11 @@ extern void ResourceOwnerRememberJIT(ResourceOwner owner,
extern void ResourceOwnerForgetJIT(ResourceOwner owner,
Datum handle);
+/* support for wait event set management */
+extern void ResourceOwnerEnlargeWESs(ResourceOwner owner);
+extern void ResourceOwnerRememberWES(ResourceOwner owner,
+ WaitEventSet *);
+extern void ResourceOwnerForgetWES(ResourceOwner owner,
+ WaitEventSet *);
+
#endif /* RESOWNER_PRIVATE_H */
--
2.16.3
From 0b3b692e677f7fd19f618582412acf9d12231bb2 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Thu, 19 Oct 2017 17:23:51 +0900
Subject: [PATCH 2/3] core side modification
---
contrib/postgres_fdw/expected/postgres_fdw.out | 100 +++++-----
src/backend/commands/explain.c | 17 ++
src/backend/executor/Makefile | 2 +-
src/backend/executor/execAsync.c | 145 ++++++++++++++
src/backend/executor/nodeAppend.c | 262 +++++++++++++++++++++----
src/backend/executor/nodeForeignscan.c | 22 ++-
src/backend/nodes/copyfuncs.c | 2 +
src/backend/nodes/outfuncs.c | 2 +
src/backend/nodes/readfuncs.c | 2 +
src/backend/optimizer/plan/createplan.c | 68 ++++++-
src/backend/postmaster/pgstat.c | 3 +
src/backend/utils/adt/ruleutils.c | 8 +-
src/include/executor/execAsync.h | 23 +++
src/include/executor/executor.h | 1 +
src/include/executor/nodeForeignscan.h | 3 +
src/include/foreign/fdwapi.h | 11 ++
src/include/nodes/execnodes.h | 18 +-
src/include/nodes/plannodes.h | 7 +
src/include/pgstat.h | 3 +-
19 files changed, 603 insertions(+), 96 deletions(-)
create mode 100644 src/backend/executor/execAsync.c
create mode 100644 src/include/executor/execAsync.h
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index bb6b1a8fdf..248aa73c0b 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -6968,12 +6968,13 @@ select * from bar where f1 in (select f1 from foo) for update;
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo
- Output: foo.ctid, foo.*, foo.tableoid, foo.f1
- -> Foreign Scan on public.foo2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2
Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-(23 rows)
+ -> Seq Scan on public.foo
+ Output: foo.ctid, foo.*, foo.tableoid, foo.f1
+(29 rows)
select * from bar where f1 in (select f1 from foo) for update;
f1 | f2
@@ -7006,12 +7007,13 @@ select * from bar where f1 in (select f1 from foo) for share;
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo
- Output: foo.ctid, foo.*, foo.tableoid, foo.f1
- -> Foreign Scan on public.foo2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2
Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-(23 rows)
+ -> Seq Scan on public.foo
+ Output: foo.ctid, foo.*, foo.tableoid, foo.f1
+(29 rows)
select * from bar where f1 in (select f1 from foo) for share;
f1 | f2
@@ -7043,9 +7045,8 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo
- Output: foo.ctid, foo.*, foo.tableoid, foo.f1
- -> Foreign Scan on public.foo2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2
Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-> Hash Join
@@ -7061,12 +7062,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo
- Output: foo.ctid, foo.*, foo.tableoid, foo.f1
- -> Foreign Scan on public.foo2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2
Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-(39 rows)
+ -> Seq Scan on public.foo
+ Output: foo.ctid, foo.*, foo.tableoid, foo.f1
+(41 rows)
update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
select tableoid::regclass, * from bar order by 1,2;
@@ -7096,14 +7098,11 @@ where bar.f1 = ss.f1;
Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1))
Hash Cond: (foo.f1 = bar.f1)
-> Append
- -> Seq Scan on public.foo
- Output: ROW(foo.f1), foo.f1
- -> Foreign Scan on public.foo2
+ Async subplans: 2
+ -> Async Foreign Scan on public.foo2
Output: ROW(foo2.f1), foo2.f1
Remote SQL: SELECT f1 FROM public.loct1
- -> Seq Scan on public.foo foo_1
- Output: ROW((foo_1.f1 + 3)), (foo_1.f1 + 3)
- -> Foreign Scan on public.foo2 foo2_1
+ -> Async Foreign Scan on public.foo2 foo2_1
Output: ROW((foo2_1.f1 + 3)), (foo2_1.f1 + 3)
Remote SQL: SELECT f1 FROM public.loct1
-> Hash
@@ -7123,17 +7122,18 @@ where bar.f1 = ss.f1;
Output: (ROW(foo.f1)), foo.f1
Sort Key: foo.f1
-> Append
- -> Seq Scan on public.foo
- Output: ROW(foo.f1), foo.f1
- -> Foreign Scan on public.foo2
+ Async subplans: 2
+ -> Async Foreign Scan on public.foo2
Output: ROW(foo2.f1), foo2.f1
Remote SQL: SELECT f1 FROM public.loct1
- -> Seq Scan on public.foo foo_1
- Output: ROW((foo_1.f1 + 3)), (foo_1.f1 + 3)
- -> Foreign Scan on public.foo2 foo2_1
+ -> Async Foreign Scan on public.foo2 foo2_1
Output: ROW((foo2_1.f1 + 3)), (foo2_1.f1 + 3)
Remote SQL: SELECT f1 FROM public.loct1
-(45 rows)
+ -> Seq Scan on public.foo
+ Output: ROW(foo.f1), foo.f1
+ -> Seq Scan on public.foo foo_1
+ Output: ROW((foo_1.f1 + 3)), (foo_1.f1 + 3)
+(47 rows)
update bar set f2 = f2 + 100
from
@@ -8155,11 +8155,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J
Sort
Sort Key: t1.a, t3.c
-> Append
- -> Foreign Scan
+ Async subplans: 2
+ -> Async Foreign Scan
Relations: ((public.ftprt1_p1 t1) INNER JOIN (public.ftprt2_p1 t2)) INNER JOIN (public.ftprt1_p1 t3)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: ((public.ftprt1_p2 t1) INNER JOIN (public.ftprt2_p2 t2)) INNER JOIN (public.ftprt1_p2 t3)
-(7 rows)
+(8 rows)
SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE
t1.a% 25 =0 ORDER BY 1,2,3;
a | b | c
@@ -8178,9 +8179,10 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10)
Sort
Sort Key: t1.a, ftprt2_p1.b, ftprt2_p1.c
-> Append
- -> Foreign Scan
+ Async subplans: 1
+ -> Async Foreign Scan
Relations: (public.ftprt1_p1 t1) LEFT JOIN (public.ftprt2_p1 fprt2)
-(5 rows)
+(6 rows)
SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) t2 ON (t1.a = t2.b and t1.b = t2.a)
WHEREt1.a < 10 ORDER BY 1,2,3;
a | b | c
@@ -8200,11 +8202,12 @@ SELECT t1,t2 FROM fprt1 t1 JOIN fprt2 t2 ON (t1.a = t2.b and t1.b = t2.a) WHERE
Sort
Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2)
-> Append
- -> Foreign Scan
+ Async subplans: 2
+ -> Async Foreign Scan
Relations: (public.ftprt1_p1 t1) INNER JOIN (public.ftprt2_p1 t2)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: (public.ftprt1_p2 t1) INNER JOIN (public.ftprt2_p2 t2)
-(7 rows)
+(8 rows)
SELECT t1,t2 FROM fprt1 t1 JOIN fprt2 t2 ON (t1.a = t2.b and t1.b = t2.a) WHERE t1.a % 25 =0 ORDER BY 1,2;
t1 | t2
@@ -8223,11 +8226,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t
Sort
Sort Key: t1.a, t1.b
-> Append
- -> Foreign Scan
+ Async subplans: 2
+ -> Async Foreign Scan
Relations: (public.ftprt1_p1 t1) INNER JOIN (public.ftprt2_p1 t2)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: (public.ftprt1_p2 t1) INNER JOIN (public.ftprt2_p2 t2)
-(7 rows)
+(8 rows)
SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE
t1.a%25= 0 ORDER BY 1,2;
a | b
@@ -8309,10 +8313,11 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O
Group Key: fpagg_tab_p1.a
Filter: (avg(fpagg_tab_p1.b) < '22'::numeric)
-> Append
- -> Foreign Scan on fpagg_tab_p1
- -> Foreign Scan on fpagg_tab_p2
- -> Foreign Scan on fpagg_tab_p3
-(9 rows)
+ Async subplans: 3
+ -> Async Foreign Scan on fpagg_tab_p1
+ -> Async Foreign Scan on fpagg_tab_p2
+ -> Async Foreign Scan on fpagg_tab_p3
+(10 rows)
-- Plan with partitionwise aggregates is enabled
SET enable_partitionwise_aggregate TO true;
@@ -8323,13 +8328,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O
Sort
Sort Key: fpagg_tab_p1.a
-> Append
- -> Foreign Scan
+ Async subplans: 3
+ -> Async Foreign Scan
Relations: Aggregate on (public.fpagg_tab_p1 pagg_tab)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: Aggregate on (public.fpagg_tab_p2 pagg_tab)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: Aggregate on (public.fpagg_tab_p3 pagg_tab)
-(9 rows)
+(10 rows)
SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1;
a | sum | min | count
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 73d94b7235..09c5327cb4 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -83,6 +83,7 @@ static void show_sort_keys(SortState *sortstate, List *ancestors,
ExplainState *es);
static void show_merge_append_keys(MergeAppendState *mstate, List *ancestors,
ExplainState *es);
+static void show_append_info(AppendState *astate, ExplainState *es);
static void show_agg_keys(AggState *astate, List *ancestors,
ExplainState *es);
static void show_grouping_sets(PlanState *planstate, Agg *agg,
@@ -1168,6 +1169,8 @@ ExplainNode(PlanState *planstate, List *ancestors,
}
if (plan->parallel_aware)
appendStringInfoString(es->str, "Parallel ");
+ if (plan->async_capable)
+ appendStringInfoString(es->str, "Async ");
appendStringInfoString(es->str, pname);
es->indent++;
}
@@ -1690,6 +1693,11 @@ ExplainNode(PlanState *planstate, List *ancestors,
case T_Hash:
show_hash_info(castNode(HashState, planstate), es);
break;
+
+ case T_Append:
+ show_append_info(castNode(AppendState, planstate), es);
+ break;
+
default:
break;
}
@@ -2027,6 +2035,15 @@ show_merge_append_keys(MergeAppendState *mstate, List *ancestors,
ancestors, es);
}
+static void
+show_append_info(AppendState *astate, ExplainState *es)
+{
+ Append *plan = (Append *) astate->ps.plan;
+
+ if (plan->nasyncplans > 0)
+ ExplainPropertyInteger("Async subplans", "", plan->nasyncplans, es);
+}
+
/*
* Show the grouping keys for an Agg node.
*/
diff --git a/src/backend/executor/Makefile b/src/backend/executor/Makefile
index cc09895fa5..8ad2adfe1c 100644
--- a/src/backend/executor/Makefile
+++ b/src/backend/executor/Makefile
@@ -12,7 +12,7 @@ subdir = src/backend/executor
top_builddir = ../../..
include $(top_builddir)/src/Makefile.global
-OBJS = execAmi.o execCurrent.o execExpr.o execExprInterp.o \
+OBJS = execAmi.o execAsync.o execCurrent.o execExpr.o execExprInterp.o \
execGrouping.o execIndexing.o execJunk.o \
execMain.o execParallel.o execPartition.o execProcnode.o \
execReplication.o execScan.o execSRF.o execTuples.o \
diff --git a/src/backend/executor/execAsync.c b/src/backend/executor/execAsync.c
new file mode 100644
index 0000000000..db477e2cf6
--- /dev/null
+++ b/src/backend/executor/execAsync.c
@@ -0,0 +1,145 @@
+/*-------------------------------------------------------------------------
+ *
+ * execAsync.c
+ * Support routines for asynchronous execution.
+ *
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ * src/backend/executor/execAsync.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "executor/execAsync.h"
+#include "executor/nodeAppend.h"
+#include "executor/nodeForeignscan.h"
+#include "miscadmin.h"
+#include "pgstat.h"
+#include "utils/memutils.h"
+#include "utils/resowner.h"
+
+void ExecAsyncSetState(PlanState *pstate, AsyncState status)
+{
+ pstate->asyncstate = status;
+}
+
+bool
+ExecAsyncConfigureWait(WaitEventSet *wes, PlanState *node,
+ void *data, bool reinit)
+{
+ switch (nodeTag(node))
+ {
+ case T_ForeignScanState:
+ return ExecForeignAsyncConfigureWait((ForeignScanState *)node,
+ wes, data, reinit);
+ break;
+ default:
+ elog(ERROR, "unrecognized node type: %d",
+ (int) nodeTag(node));
+ }
+}
+
+/*
+ * struct for memory context callback argument used in ExecAsyncEventWait
+ */
+typedef struct {
+ int **p_refind;
+ int *p_refindsize;
+} ExecAsync_mcbarg;
+
+/*
+ * callback function to reset static variables pointing to the memory in
+ * TopTransactionContext in ExecAsyncEventWait.
+ */
+static void ExecAsyncMemoryContextCallback(void *arg)
+{
+ /* arg is the address of the variable refind in ExecAsyncEventWait */
+ ExecAsync_mcbarg *mcbarg = (ExecAsync_mcbarg *) arg;
+ *mcbarg->p_refind = NULL;
+ *mcbarg->p_refindsize = 0;
+}
+
+#define EVENT_BUFFER_SIZE 16
+
+Bitmapset *
+ExecAsyncEventWait(PlanState **nodes, Bitmapset *waitnodes, long timeout)
+{
+ static int *refind = NULL;
+ static int refindsize = 0;
+ WaitEventSet *wes;
+ WaitEvent occurred_event[EVENT_BUFFER_SIZE];
+ int noccurred = 0;
+ Bitmapset *fired_events = NULL;
+ int i;
+ int n;
+
+ n = bms_num_members(waitnodes);
+ wes = CreateWaitEventSet(TopTransactionContext,
+ TopTransactionResourceOwner, n);
+ if (refindsize < n)
+ {
+ if (refindsize == 0)
+ refindsize = EVENT_BUFFER_SIZE; /* XXX */
+ while (refindsize < n)
+ refindsize *= 2;
+ if (refind)
+ refind = (int *) repalloc(refind, refindsize * sizeof(int));
+ else
+ {
+ static ExecAsync_mcbarg mcb_arg =
+ { &refind, &refindsize };
+ static MemoryContextCallback mcb =
+ { ExecAsyncMemoryContextCallback, (void *)&mcb_arg, NULL };
+ MemoryContext oldctxt =
+ MemoryContextSwitchTo(TopTransactionContext);
+
+ /*
+ * refind points to a memory block in
+ * TopTransactionContext. Register a callback to reset it.
+ */
+ MemoryContextRegisterResetCallback(TopTransactionContext, &mcb);
+ refind = (int *) palloc(refindsize * sizeof(int));
+ MemoryContextSwitchTo(oldctxt);
+ }
+ }
+
+ n = 0;
+ for (i = bms_next_member(waitnodes, -1) ; i >= 0 ;
+ i = bms_next_member(waitnodes, i))
+ {
+ refind[i] = i;
+ if (ExecAsyncConfigureWait(wes, nodes[i], refind + i, true))
+ n++;
+ }
+
+ if (n == 0)
+ {
+ FreeWaitEventSet(wes);
+ return NULL;
+ }
+
+ noccurred = WaitEventSetWait(wes, timeout, occurred_event,
+ EVENT_BUFFER_SIZE,
+ WAIT_EVENT_ASYNC_WAIT);
+ FreeWaitEventSet(wes);
+ if (noccurred == 0)
+ return NULL;
+
+ for (i = 0 ; i < noccurred ; i++)
+ {
+ WaitEvent *w = &occurred_event[i];
+
+ if ((w->events & (WL_SOCKET_READABLE | WL_SOCKET_WRITEABLE)) != 0)
+ {
+ int n = *(int*)w->user_data;
+
+ fired_events = bms_add_member(fired_events, n);
+ }
+ }
+
+ return fired_events;
+}
diff --git a/src/backend/executor/nodeAppend.c b/src/backend/executor/nodeAppend.c
index 6bc3e470bf..ed8612dd37 100644
--- a/src/backend/executor/nodeAppend.c
+++ b/src/backend/executor/nodeAppend.c
@@ -60,6 +60,7 @@
#include "executor/execdebug.h"
#include "executor/execPartition.h"
#include "executor/nodeAppend.h"
+#include "executor/execAsync.h"
#include "miscadmin.h"
/* Shared state for parallel-aware Append. */
@@ -81,6 +82,7 @@ struct ParallelAppendState
#define NO_MATCHING_SUBPLANS -2
static TupleTableSlot *ExecAppend(PlanState *pstate);
+static TupleTableSlot *ExecAppendAsync(PlanState *pstate);
static bool choose_next_subplan_locally(AppendState *node);
static bool choose_next_subplan_for_leader(AppendState *node);
static bool choose_next_subplan_for_worker(AppendState *node);
@@ -104,13 +106,14 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
PlanState **appendplanstates;
Bitmapset *validsubplans;
int nplans;
+ int nasyncplans;
int firstvalid;
int i,
j;
ListCell *lc;
/* check for unsupported flags */
- Assert(!(eflags & EXEC_FLAG_MARK));
+ Assert(!(eflags & (EXEC_FLAG_MARK | EXEC_FLAG_ASYNC)));
/*
* Lock the non-leaf tables in the partition tree controlled by this node.
@@ -123,10 +126,15 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
*/
appendstate->ps.plan = (Plan *) node;
appendstate->ps.state = estate;
- appendstate->ps.ExecProcNode = ExecAppend;
+
+ /* choose appropriate version of Exec function */
+ if (node->nasyncplans == 0)
+ appendstate->ps.ExecProcNode = ExecAppend;
+ else
+ appendstate->ps.ExecProcNode = ExecAppendAsync;
/* Let choose_next_subplan_* function handle setting the first subplan */
- appendstate->as_whichplan = INVALID_SUBPLAN_INDEX;
+ appendstate->as_whichsyncplan = INVALID_SUBPLAN_INDEX;
/* If run-time partition pruning is enabled, then set that up now */
if (node->part_prune_infos != NIL)
@@ -159,7 +167,7 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
*/
if (bms_is_empty(validsubplans))
{
- appendstate->as_whichplan = NO_MATCHING_SUBPLANS;
+ appendstate->as_whichsyncplan = NO_MATCHING_SUBPLANS;
/* Mark the first as valid so that it's initialized below */
validsubplans = bms_make_singleton(0);
@@ -213,11 +221,20 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
*/
j = i = 0;
firstvalid = nplans;
+ nasyncplans = 0;
foreach(lc, node->appendplans)
{
if (bms_is_member(i, validsubplans))
{
Plan *initNode = (Plan *) lfirst(lc);
+ int sub_eflags = eflags;
+
+ /* Let async-capable subplans run asynchronously */
+ if (i < node->nasyncplans)
+ {
+ sub_eflags |= EXEC_FLAG_ASYNC;
+ nasyncplans++;
+ }
/*
* Record the lowest appendplans index which is a valid partial
@@ -226,7 +243,7 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
if (i >= node->first_partial_plan && j < firstvalid)
firstvalid = j;
- appendplanstates[j++] = ExecInitNode(initNode, estate, eflags);
+ appendplanstates[j++] = ExecInitNode(initNode, estate, sub_eflags);
}
i++;
}
@@ -235,6 +252,21 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
appendstate->appendplans = appendplanstates;
appendstate->as_nplans = nplans;
+ /* fill in async stuff */
+ appendstate->as_nasyncplans = nasyncplans;
+ appendstate->as_syncdone = (nasyncplans == nplans);
+
+ if (appendstate->as_nasyncplans)
+ {
+ appendstate->as_asyncresult = (TupleTableSlot **)
+ palloc0(node->nasyncplans * sizeof(TupleTableSlot *));
+
+ /* initially, all async requests need a request */
+ for (i = 0; i < appendstate->as_nasyncplans; ++i)
+ appendstate->as_needrequest =
+ bms_add_member(appendstate->as_needrequest, i);
+ }
+
/*
* Miscellaneous initialization
*/
@@ -258,21 +290,23 @@ ExecAppend(PlanState *pstate)
{
AppendState *node = castNode(AppendState, pstate);
- if (node->as_whichplan < 0)
+ if (node->as_whichsyncplan < 0)
{
/*
* If no subplan has been chosen, we must choose one before
* proceeding.
*/
- if (node->as_whichplan == INVALID_SUBPLAN_INDEX &&
+ if (node->as_whichsyncplan == INVALID_SUBPLAN_INDEX &&
!node->choose_next_subplan(node))
return ExecClearTuple(node->ps.ps_ResultTupleSlot);
/* Nothing to do if there are no matching subplans */
- else if (node->as_whichplan == NO_MATCHING_SUBPLANS)
+ else if (node->as_whichsyncplan == NO_MATCHING_SUBPLANS)
return ExecClearTuple(node->ps.ps_ResultTupleSlot);
}
+ Assert(node->as_nasyncplans == 0);
+
for (;;)
{
PlanState *subnode;
@@ -283,8 +317,9 @@ ExecAppend(PlanState *pstate)
/*
* figure out which subplan we are currently processing
*/
- Assert(node->as_whichplan >= 0 && node->as_whichplan < node->as_nplans);
- subnode = node->appendplans[node->as_whichplan];
+ Assert(node->as_whichsyncplan >= 0 &&
+ node->as_whichsyncplan < node->as_nplans);
+ subnode = node->appendplans[node->as_whichsyncplan];
/*
* get a tuple from the subplan
@@ -307,6 +342,156 @@ ExecAppend(PlanState *pstate)
}
}
+static TupleTableSlot *
+ExecAppendAsync(PlanState *pstate)
+{
+ AppendState *node = castNode(AppendState, pstate);
+ Bitmapset *needrequest;
+ int i;
+
+ Assert(node->as_nasyncplans > 0);
+
+ if (node->as_nasyncresult > 0)
+ {
+ --node->as_nasyncresult;
+ return node->as_asyncresult[node->as_nasyncresult];
+ }
+
+ needrequest = node->as_needrequest;
+ node->as_needrequest = NULL;
+ while ((i = bms_first_member(needrequest)) >= 0)
+ {
+ TupleTableSlot *slot;
+ PlanState *subnode = node->appendplans[i];
+
+ slot = ExecProcNode(subnode);
+ if (subnode->asyncstate == AS_AVAILABLE)
+ {
+ if (!TupIsNull(slot))
+ {
+ node->as_asyncresult[node->as_nasyncresult++] = slot;
+ node->as_needrequest = bms_add_member(node->as_needrequest, i);
+ }
+ }
+ else
+ node->as_pending_async = bms_add_member(node->as_pending_async, i);
+ }
+ bms_free(needrequest);
+
+ for (;;)
+ {
+ TupleTableSlot *result;
+
+ /* return now if a result is available */
+ if (node->as_nasyncresult > 0)
+ {
+ --node->as_nasyncresult;
+ return node->as_asyncresult[node->as_nasyncresult];
+ }
+
+ while (!bms_is_empty(node->as_pending_async))
+ {
+ long timeout = node->as_syncdone ? -1 : 0;
+ Bitmapset *fired;
+ int i;
+
+ fired = ExecAsyncEventWait(node->appendplans,
+ node->as_pending_async,
+ timeout);
+ Assert(!node->as_syncdone || !bms_is_empty(fired));
+
+ while ((i = bms_first_member(fired)) >= 0)
+ {
+ TupleTableSlot *slot;
+ PlanState *subnode = node->appendplans[i];
+ slot = ExecProcNode(subnode);
+ if (subnode->asyncstate == AS_AVAILABLE)
+ {
+ if (!TupIsNull(slot))
+ {
+ node->as_asyncresult[node->as_nasyncresult++] = slot;
+ node->as_needrequest =
+ bms_add_member(node->as_needrequest, i);
+ }
+ node->as_pending_async =
+ bms_del_member(node->as_pending_async, i);
+ }
+ }
+ bms_free(fired);
+
+ /* return now if a result is available */
+ if (node->as_nasyncresult > 0)
+ {
+ --node->as_nasyncresult;
+ return node->as_asyncresult[node->as_nasyncresult];
+ }
+
+ if (!node->as_syncdone)
+ break;
+ }
+
+ /*
+ * If there is no asynchronous activity still pending and the
+ * synchronous activity is also complete, we're totally done scanning
+ * this node. Otherwise, we're done with the asynchronous stuff but
+ * must continue scanning the synchronous children.
+ */
+ if (node->as_syncdone)
+ {
+ Assert(bms_is_empty(node->as_pending_async));
+ return ExecClearTuple(node->ps.ps_ResultTupleSlot);
+ }
+
+ /*
+ * get a tuple from the subplan
+ */
+
+ if (node->as_whichsyncplan < 0)
+ {
+ /*
+ * If no subplan has been chosen, we must choose one before
+ * proceeding.
+ */
+ if (node->as_whichsyncplan == INVALID_SUBPLAN_INDEX &&
+ !node->choose_next_subplan(node))
+ return ExecClearTuple(node->ps.ps_ResultTupleSlot);
+
+ /* Nothing to do if there are no matching subplans */
+ else if (node->as_whichsyncplan == NO_MATCHING_SUBPLANS)
+ return ExecClearTuple(node->ps.ps_ResultTupleSlot);
+ }
+
+ result = ExecProcNode(node->appendplans[node->as_whichsyncplan]);
+
+ if (!TupIsNull(result))
+ {
+ /*
+ * If the subplan gave us something then return it as-is. We do
+ * NOT make use of the result slot that was set up in
+ * ExecInitAppend; there's no need for it.
+ */
+ return result;
+ }
+
+ /*
+ * Go on to the "next" subplan in the appropriate direction. If no
+ * more subplans, return the empty slot set up for us by
+ * ExecInitAppend, unless there are async plans we have yet to finish.
+ */
+ if (!node->choose_next_subplan(node))
+ {
+ node->as_syncdone = true;
+ if (bms_is_empty(node->as_pending_async))
+ {
+ Assert(bms_is_empty(node->as_needrequest));
+ return ExecClearTuple(node->ps.ps_ResultTupleSlot);
+ }
+ }
+
+ /* Else loop back and try to get a tuple from the new subplan */
+ }
+}
+
/* ----------------------------------------------------------------
* ExecEndAppend
*
@@ -353,6 +538,15 @@ ExecReScanAppend(AppendState *node)
node->as_valid_subplans = NULL;
}
+ /* Reset async state. */
+ for (i = 0; i < node->as_nasyncplans; ++i)
+ {
+ ExecShutdownNode(node->appendplans[i]);
+ node->as_needrequest = bms_add_member(node->as_needrequest, i);
+ }
+ node->as_nasyncresult = 0;
+ node->as_syncdone = (node->as_nasyncplans == node->as_nplans);
+
for (i = 0; i < node->as_nplans; i++)
{
PlanState *subnode = node->appendplans[i];
@@ -373,7 +567,7 @@ ExecReScanAppend(AppendState *node)
}
/* Let choose_next_subplan_* function handle setting the first subplan */
- node->as_whichplan = INVALID_SUBPLAN_INDEX;
+ node->as_whichsyncplan = INVALID_SUBPLAN_INDEX;
}
/* ----------------------------------------------------------------
@@ -461,7 +655,7 @@ ExecAppendInitializeWorker(AppendState *node, ParallelWorkerContext *pwcxt)
static bool
choose_next_subplan_locally(AppendState *node)
{
- int whichplan = node->as_whichplan;
+ int whichplan = node->as_whichsyncplan;
int nextplan;
/* We should never be called when there are no subplans */
@@ -494,7 +688,7 @@ choose_next_subplan_locally(AppendState *node)
if (nextplan < 0)
return false;
- node->as_whichplan = nextplan;
+ node->as_whichsyncplan = nextplan;
return true;
}
@@ -516,19 +710,19 @@ choose_next_subplan_for_leader(AppendState *node)
Assert(ScanDirectionIsForward(node->ps.state->es_direction));
/* We should never be called when there are no subplans */
- Assert(node->as_whichplan != NO_MATCHING_SUBPLANS);
+ Assert(node->as_whichsyncplan != NO_MATCHING_SUBPLANS);
LWLockAcquire(&pstate->pa_lock, LW_EXCLUSIVE);
- if (node->as_whichplan != INVALID_SUBPLAN_INDEX)
+ if (node->as_whichsyncplan != INVALID_SUBPLAN_INDEX)
{
/* Mark just-completed subplan as finished. */
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
}
else
{
/* Start with last subplan. */
- node->as_whichplan = node->as_nplans - 1;
+ node->as_whichsyncplan = node->as_nplans - 1;
/*
* If we've yet to determine the valid subplans for these parameters
@@ -549,12 +743,12 @@ choose_next_subplan_for_leader(AppendState *node)
}
/* Loop until we find a subplan to execute. */
- while (pstate->pa_finished[node->as_whichplan])
+ while (pstate->pa_finished[node->as_whichsyncplan])
{
- if (node->as_whichplan == 0)
+ if (node->as_whichsyncplan == 0)
{
pstate->pa_next_plan = INVALID_SUBPLAN_INDEX;
- node->as_whichplan = INVALID_SUBPLAN_INDEX;
+ node->as_whichsyncplan = INVALID_SUBPLAN_INDEX;
LWLockRelease(&pstate->pa_lock);
return false;
}
@@ -563,12 +757,12 @@ choose_next_subplan_for_leader(AppendState *node)
* We needn't pay attention to as_valid_subplans here as all invalid
* plans have been marked as finished.
*/
- node->as_whichplan--;
+ node->as_whichsyncplan--;
}
/* If non-partial, immediately mark as finished. */
- if (node->as_whichplan < node->as_first_partial_plan)
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ if (node->as_whichsyncplan < node->as_first_partial_plan)
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
LWLockRelease(&pstate->pa_lock);
@@ -597,13 +791,13 @@ choose_next_subplan_for_worker(AppendState *node)
Assert(ScanDirectionIsForward(node->ps.state->es_direction));
/* We should never be called when there are no subplans */
- Assert(node->as_whichplan != NO_MATCHING_SUBPLANS);
+ Assert(node->as_whichsyncplan != NO_MATCHING_SUBPLANS);
LWLockAcquire(&pstate->pa_lock, LW_EXCLUSIVE);
/* Mark just-completed subplan as finished. */
- if (node->as_whichplan != INVALID_SUBPLAN_INDEX)
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ if (node->as_whichsyncplan != INVALID_SUBPLAN_INDEX)
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
/*
* If we've yet to determine the valid subplans for these parameters then
@@ -625,7 +819,7 @@ choose_next_subplan_for_worker(AppendState *node)
}
/* Save the plan from which we are starting the search. */
- node->as_whichplan = pstate->pa_next_plan;
+ node->as_whichsyncplan = pstate->pa_next_plan;
/* Loop until we find a valid subplan to execute. */
while (pstate->pa_finished[pstate->pa_next_plan])
@@ -639,7 +833,7 @@ choose_next_subplan_for_worker(AppendState *node)
/* Advance to the next valid plan. */
pstate->pa_next_plan = nextplan;
}
- else if (node->as_whichplan > node->as_first_partial_plan)
+ else if (node->as_whichsyncplan > node->as_first_partial_plan)
{
/*
* Try looping back to the first valid partial plan, if there is
@@ -648,7 +842,7 @@ choose_next_subplan_for_worker(AppendState *node)
nextplan = bms_next_member(node->as_valid_subplans,
node->as_first_partial_plan - 1);
pstate->pa_next_plan =
- nextplan < 0 ? node->as_whichplan : nextplan;
+ nextplan < 0 ? node->as_whichsyncplan : nextplan;
}
else
{
@@ -656,10 +850,10 @@ choose_next_subplan_for_worker(AppendState *node)
* At last plan, and either there are no partial plans or we've
* tried them all. Arrange to bail out.
*/
- pstate->pa_next_plan = node->as_whichplan;
+ pstate->pa_next_plan = node->as_whichsyncplan;
}
- if (pstate->pa_next_plan == node->as_whichplan)
+ if (pstate->pa_next_plan == node->as_whichsyncplan)
{
/* We've tried everything! */
pstate->pa_next_plan = INVALID_SUBPLAN_INDEX;
@@ -669,7 +863,7 @@ choose_next_subplan_for_worker(AppendState *node)
}
/* Pick the plan we found, and advance pa_next_plan one more time. */
- node->as_whichplan = pstate->pa_next_plan;
+ node->as_whichsyncplan = pstate->pa_next_plan;
pstate->pa_next_plan = bms_next_member(node->as_valid_subplans,
pstate->pa_next_plan);
@@ -696,8 +890,8 @@ choose_next_subplan_for_worker(AppendState *node)
}
/* If non-partial, immediately mark as finished. */
- if (node->as_whichplan < node->as_first_partial_plan)
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ if (node->as_whichsyncplan < node->as_first_partial_plan)
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
LWLockRelease(&pstate->pa_lock);
diff --git a/src/backend/executor/nodeForeignscan.c b/src/backend/executor/nodeForeignscan.c
index a2a28b7ec2..915deb7080 100644
--- a/src/backend/executor/nodeForeignscan.c
+++ b/src/backend/executor/nodeForeignscan.c
@@ -123,7 +123,6 @@ ExecForeignScan(PlanState *pstate)
(ExecScanRecheckMtd) ForeignRecheck);
}
-
/* ----------------------------------------------------------------
* ExecInitForeignScan
* ----------------------------------------------------------------
@@ -147,6 +146,10 @@ ExecInitForeignScan(ForeignScan *node, EState *estate, int eflags)
scanstate->ss.ps.plan = (Plan *) node;
scanstate->ss.ps.state = estate;
scanstate->ss.ps.ExecProcNode = ExecForeignScan;
+ scanstate->ss.ps.asyncstate = AS_AVAILABLE;
+
+ if ((eflags & EXEC_FLAG_ASYNC) != 0)
+ scanstate->fs_async = true;
/*
* Miscellaneous initialization
@@ -387,3 +390,20 @@ ExecShutdownForeignScan(ForeignScanState *node)
if (fdwroutine->ShutdownForeignScan)
fdwroutine->ShutdownForeignScan(node);
}
+
+/* ----------------------------------------------------------------
+ * ExecAsyncForeignScanConfigureWait
+ *
+ * In async mode, configure for a wait
+ * ----------------------------------------------------------------
+ */
+bool
+ExecForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes,
+ void *caller_data, bool reinit)
+{
+ FdwRoutine *fdwroutine = node->fdwroutine;
+
+ Assert(fdwroutine->ForeignAsyncConfigureWait != NULL);
+ return fdwroutine->ForeignAsyncConfigureWait(node, wes,
+ caller_data, reinit);
+}
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 7c045a7afe..8304dd5b17 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -246,6 +246,8 @@ _copyAppend(const Append *from)
COPY_NODE_FIELD(appendplans);
COPY_SCALAR_FIELD(first_partial_plan);
COPY_NODE_FIELD(part_prune_infos);
+ COPY_SCALAR_FIELD(nasyncplans);
+ COPY_SCALAR_FIELD(referent);
return newnode;
}
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 1da9d7ed15..ed655f4ccb 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -403,6 +403,8 @@ _outAppend(StringInfo str, const Append *node)
WRITE_NODE_FIELD(appendplans);
WRITE_INT_FIELD(first_partial_plan);
WRITE_NODE_FIELD(part_prune_infos);
+ WRITE_INT_FIELD(nasyncplans);
+ WRITE_INT_FIELD(referent);
}
static void
diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index 2826cec2f8..fb4ae251de 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -1652,6 +1652,8 @@ _readAppend(void)
READ_NODE_FIELD(appendplans);
READ_INT_FIELD(first_partial_plan);
READ_NODE_FIELD(part_prune_infos);
+ READ_INT_FIELD(nasyncplans);
+ READ_INT_FIELD(referent);
READ_DONE();
}
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 0317763f43..eda3420d02 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -211,7 +211,9 @@ static NamedTuplestoreScan *make_namedtuplestorescan(List *qptlist, List *qpqual
static WorkTableScan *make_worktablescan(List *qptlist, List *qpqual,
Index scanrelid, int wtParam);
static Append *make_append(List *appendplans, int first_partial_plan,
- List *tlist, List *partitioned_rels, List *partpruneinfos);
+ int nasyncplans, int referent,
+ List *tlist,
+ List *partitioned_rels, List *partpruneinfos);
static RecursiveUnion *make_recursive_union(List *tlist,
Plan *lefttree,
Plan *righttree,
@@ -294,6 +296,7 @@ static ModifyTable *make_modifytable(PlannerInfo *root,
List *rowMarks, OnConflictExpr *onconflict, int epqParam);
static GatherMerge *create_gather_merge_plan(PlannerInfo *root,
GatherMergePath *best_path);
+static bool is_async_capable_path(Path *path);
/*
@@ -1036,10 +1039,14 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path)
{
Append *plan;
List *tlist = build_path_tlist(root, &best_path->path);
- List *subplans = NIL;
+ List *asyncplans = NIL;
+ List *syncplans = NIL;
ListCell *subpaths;
RelOptInfo *rel = best_path->path.parent;
List *partpruneinfos = NIL;
+ int nasyncplans = 0;
+ bool first = true;
+ bool referent_is_sync = true;
/*
* The subpaths list could be empty, if every child was proven empty by
@@ -1074,7 +1081,22 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path)
/* Must insist that all children return the same tlist */
subplan = create_plan_recurse(root, subpath, CP_EXACT_TLIST);
- subplans = lappend(subplans, subplan);
+ /*
+ * Classify as async-capable or not. If we have decided to run the
+ * chidlren in parallel, we cannot any one of them run asynchronously.
+ */
+ if (!best_path->path.parallel_safe && is_async_capable_path(subpath))
+ {
+ subplan->async_capable = true;
+ asyncplans = lappend(asyncplans, subplan);
+ ++nasyncplans;
+ if (first)
+ referent_is_sync = false;
+ }
+ else
+ syncplans = lappend(syncplans, subplan);
+
+ first = false;
}
if (enable_partition_pruning &&
@@ -1117,9 +1139,10 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path)
* parent-rel Vars it'll be asked to emit.
*/
- plan = make_append(subplans, best_path->first_partial_path,
- tlist, best_path->partitioned_rels,
- partpruneinfos);
+ plan = make_append(list_concat(asyncplans, syncplans),
+ best_path->first_partial_path, nasyncplans,
+ referent_is_sync ? nasyncplans : 0, tlist,
+ best_path->partitioned_rels, partpruneinfos);
copy_generic_path_info(&plan->plan, (Path *) best_path);
@@ -5414,9 +5437,9 @@ make_foreignscan(List *qptlist,
}
static Append *
-make_append(List *appendplans, int first_partial_plan,
- List *tlist, List *partitioned_rels,
- List *partpruneinfos)
+make_append(List *appendplans, int first_partial_plan, int nasyncplans,
+ int referent, List *tlist,
+ List *partitioned_rels, List *partpruneinfos)
{
Append *node = makeNode(Append);
Plan *plan = &node->plan;
@@ -5429,6 +5452,9 @@ make_append(List *appendplans, int first_partial_plan,
node->appendplans = appendplans;
node->first_partial_plan = first_partial_plan;
node->part_prune_infos = partpruneinfos;
+ node->nasyncplans = nasyncplans;
+ node->referent = referent;
+
return node;
}
@@ -6773,3 +6799,27 @@ is_projection_capable_plan(Plan *plan)
}
return true;
}
+
+/*
+ * is_projection_capable_path
+ * Check whether a given Path node is async-capable.
+ */
+static bool
+is_async_capable_path(Path *path)
+{
+ switch (nodeTag(path))
+ {
+ case T_ForeignPath:
+ {
+ FdwRoutine *fdwroutine = path->parent->fdwroutine;
+
+ Assert(fdwroutine != NULL);
+ if (fdwroutine->IsForeignPathAsyncCapable != NULL &&
+ fdwroutine->IsForeignPathAsyncCapable((ForeignPath *) path))
+ return true;
+ }
+ default:
+ break;
+ }
+ return false;
+}
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 084573e77c..7aef97ca97 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -3683,6 +3683,9 @@ pgstat_get_wait_ipc(WaitEventIPC w)
case WAIT_EVENT_SYNC_REP:
event_name = "SyncRep";
break;
+ case WAIT_EVENT_ASYNC_WAIT:
+ event_name = "AsyncExecWait";
+ break;
/* no default case, so that compiler will warn */
}
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 065238b0fe..fe202cbfea 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -4513,7 +4513,7 @@ set_deparse_planstate(deparse_namespace *dpns, PlanState *ps)
dpns->planstate = ps;
/*
- * We special-case Append and MergeAppend to pretend that the first child
+ * We special-case Append and MergeAppend to pretend that a specific child
* plan is the OUTER referent; we have to interpret OUTER Vars in their
* tlists according to one of the children, and the first one is the most
* natural choice. Likewise special-case ModifyTable to pretend that the
@@ -4521,7 +4521,11 @@ set_deparse_planstate(deparse_namespace *dpns, PlanState *ps)
* lists containing references to non-target relations.
*/
if (IsA(ps, AppendState))
- dpns->outer_planstate = ((AppendState *) ps)->appendplans[0];
+ {
+ AppendState *aps = (AppendState *) ps;
+ Append *app = (Append *) ps->plan;
+ dpns->outer_planstate = aps->appendplans[app->referent];
+ }
else if (IsA(ps, MergeAppendState))
dpns->outer_planstate = ((MergeAppendState *) ps)->mergeplans[0];
else if (IsA(ps, ModifyTableState))
diff --git a/src/include/executor/execAsync.h b/src/include/executor/execAsync.h
new file mode 100644
index 0000000000..5fd67d9004
--- /dev/null
+++ b/src/include/executor/execAsync.h
@@ -0,0 +1,23 @@
+/*--------------------------------------------------------------------
+ * execAsync.c
+ * Support functions for asynchronous query execution
+ *
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ * src/backend/executor/execAsync.c
+ *--------------------------------------------------------------------
+ */
+#ifndef EXECASYNC_H
+#define EXECASYNC_H
+
+#include "nodes/execnodes.h"
+#include "storage/latch.h"
+
+extern void ExecAsyncSetState(PlanState *pstate, AsyncState status);
+extern bool ExecAsyncConfigureWait(WaitEventSet *wes, PlanState *node,
+ void *data, bool reinit);
+extern Bitmapset *ExecAsyncEventWait(PlanState **nodes, Bitmapset *waitnodes,
+ long timeout);
+#endif /* EXECASYNC_H */
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index a7ea3c7d10..8e9d87669f 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -63,6 +63,7 @@
#define EXEC_FLAG_WITH_OIDS 0x0020 /* force OIDs in returned tuples */
#define EXEC_FLAG_WITHOUT_OIDS 0x0040 /* force no OIDs in returned tuples */
#define EXEC_FLAG_WITH_NO_DATA 0x0080 /* rel scannability doesn't matter */
+#define EXEC_FLAG_ASYNC 0x0100 /* request async execution */
/* Hook for plugins to get control in ExecutorStart() */
diff --git a/src/include/executor/nodeForeignscan.h b/src/include/executor/nodeForeignscan.h
index ccb66be733..67abf8e52e 100644
--- a/src/include/executor/nodeForeignscan.h
+++ b/src/include/executor/nodeForeignscan.h
@@ -30,5 +30,8 @@ extern void ExecForeignScanReInitializeDSM(ForeignScanState *node,
extern void ExecForeignScanInitializeWorker(ForeignScanState *node,
ParallelWorkerContext *pwcxt);
extern void ExecShutdownForeignScan(ForeignScanState *node);
+extern bool ExecForeignAsyncConfigureWait(ForeignScanState *node,
+ WaitEventSet *wes,
+ void *caller_data, bool reinit);
#endif /* NODEFOREIGNSCAN_H */
diff --git a/src/include/foreign/fdwapi.h b/src/include/foreign/fdwapi.h
index c14eb546c6..c00e9621fb 100644
--- a/src/include/foreign/fdwapi.h
+++ b/src/include/foreign/fdwapi.h
@@ -168,6 +168,11 @@ typedef bool (*IsForeignScanParallelSafe_function) (PlannerInfo *root,
typedef List *(*ReparameterizeForeignPathByChild_function) (PlannerInfo *root,
List *fdw_private,
RelOptInfo *child_rel);
+typedef bool (*IsForeignPathAsyncCapable_function) (ForeignPath *path);
+typedef bool (*ForeignAsyncConfigureWait_function) (ForeignScanState *node,
+ WaitEventSet *wes,
+ void *caller_data,
+ bool reinit);
/*
* FdwRoutine is the struct returned by a foreign-data wrapper's handler
@@ -189,6 +194,7 @@ typedef struct FdwRoutine
GetForeignPlan_function GetForeignPlan;
BeginForeignScan_function BeginForeignScan;
IterateForeignScan_function IterateForeignScan;
+ IterateForeignScan_function IterateForeignScanAsync;
ReScanForeignScan_function ReScanForeignScan;
EndForeignScan_function EndForeignScan;
@@ -241,6 +247,11 @@ typedef struct FdwRoutine
InitializeDSMForeignScan_function InitializeDSMForeignScan;
ReInitializeDSMForeignScan_function ReInitializeDSMForeignScan;
InitializeWorkerForeignScan_function InitializeWorkerForeignScan;
+
+ /* Support functions for asynchronous execution */
+ IsForeignPathAsyncCapable_function IsForeignPathAsyncCapable;
+ ForeignAsyncConfigureWait_function ForeignAsyncConfigureWait;
+
ShutdownForeignScan_function ShutdownForeignScan;
/* Support functions for path reparameterization. */
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index da7f52cab0..56bfe3f442 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -905,6 +905,12 @@ typedef TupleTableSlot *(*ExecProcNodeMtd) (struct PlanState *pstate);
* abstract superclass for all PlanState-type nodes.
* ----------------
*/
+typedef enum AsyncState
+{
+ AS_AVAILABLE,
+ AS_WAITING
+} AsyncState;
+
typedef struct PlanState
{
NodeTag type;
@@ -953,6 +959,9 @@ typedef struct PlanState
* descriptor, without encoding knowledge about all executor nodes.
*/
TupleDesc scandesc;
+
+ AsyncState asyncstate;
+ int32 padding; /* to keep alignment of derived types */
} PlanState;
/* ----------------
@@ -1087,14 +1096,20 @@ struct AppendState
PlanState ps; /* its first field is NodeTag */
PlanState **appendplans; /* array of PlanStates for my inputs */
int as_nplans;
- int as_whichplan;
+ int as_whichsyncplan; /* which sync plan is being executed */
int as_first_partial_plan; /* Index of 'appendplans' containing
* the first partial plan */
+ int as_nasyncplans; /* # of async-capable children */
ParallelAppendState *as_pstate; /* parallel coordination info */
Size pstate_len; /* size of parallel coordination info */
struct PartitionPruneState *as_prune_state;
Bitmapset *as_valid_subplans;
bool (*choose_next_subplan) (AppendState *);
+ bool as_syncdone; /* all synchronous plans done? */
+ Bitmapset *as_needrequest; /* async plans needing a new request */
+ Bitmapset *as_pending_async; /* pending async plans */
+ TupleTableSlot **as_asyncresult; /* unreturned results of async plans */
+ int as_nasyncresult; /* # of valid entries in as_asyncresult */
};
/* ----------------
@@ -1643,6 +1658,7 @@ typedef struct ForeignScanState
Size pscan_len; /* size of parallel coordination information */
/* use struct pointer to avoid including fdwapi.h here */
struct FdwRoutine *fdwroutine;
+ bool fs_async;
void *fdw_state; /* foreign-data wrapper can keep state here */
} ForeignScanState;
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
index f2dda82e66..8a64c037c9 100644
--- a/src/include/nodes/plannodes.h
+++ b/src/include/nodes/plannodes.h
@@ -139,6 +139,11 @@ typedef struct Plan
bool parallel_aware; /* engage parallel-aware logic? */
bool parallel_safe; /* OK to use as part of parallel plan? */
+ /*
+ * information needed for asynchronous execution
+ */
+ bool async_capable; /* engage asyncronous execution logic? */
+
/*
* Common structural data for all Plan types.
*/
@@ -262,6 +267,8 @@ typedef struct Append
* Mapping details for run-time subplan pruning, one per partitioned_rels
*/
List *part_prune_infos;
+ int nasyncplans; /* # of async plans, always at start of list */
+ int referent; /* index of inheritance tree referent */
} Append;
/* ----------------
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index be2f59239b..6f4583b46c 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -832,7 +832,8 @@ typedef enum
WAIT_EVENT_REPLICATION_ORIGIN_DROP,
WAIT_EVENT_REPLICATION_SLOT_DROP,
WAIT_EVENT_SAFE_SNAPSHOT,
- WAIT_EVENT_SYNC_REP
+ WAIT_EVENT_SYNC_REP,
+ WAIT_EVENT_ASYNC_WAIT
} WaitEventIPC;
/* ----------
--
2.16.3
From 072f6af8a2b394402e753a65569d64668e2cfe86 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Thu, 19 Oct 2017 17:24:07 +0900
Subject: [PATCH 3/3] async postgres_fdw
---
contrib/postgres_fdw/connection.c | 26 ++
contrib/postgres_fdw/expected/postgres_fdw.out | 100 ++--
contrib/postgres_fdw/postgres_fdw.c | 619 ++++++++++++++++++++++---
contrib/postgres_fdw/postgres_fdw.h | 2 +
contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +-
5 files changed, 628 insertions(+), 139 deletions(-)
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index fe4893a8e0..da7c826e4f 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -58,6 +58,7 @@ typedef struct ConnCacheEntry
bool invalidated; /* true if reconnect is pending */
uint32 server_hashvalue; /* hash value of foreign server OID */
uint32 mapping_hashvalue; /* hash value of user mapping OID */
+ void *storage; /* connection specific storage */
} ConnCacheEntry;
/*
@@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt)
elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)",
entry->conn, server->servername, user->umid, user->userid);
+ entry->storage = NULL;
}
/*
@@ -215,6 +217,30 @@ GetConnection(UserMapping *user, bool will_prep_stmt)
return entry->conn;
}
+/*
+ * Rerturns the connection specific storage for this user. Allocate with
+ * initsize if not exists.
+ */
+void *
+GetConnectionSpecificStorage(UserMapping *user, size_t initsize)
+{
+ bool found;
+ ConnCacheEntry *entry;
+ ConnCacheKey key;
+
+ key = user->umid;
+ entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found);
+ Assert(found);
+
+ if (entry->storage == NULL)
+ {
+ entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize);
+ memset(entry->storage, 0, initsize);
+ }
+
+ return entry->storage;
+}
+
/*
* Connect to remote server using specified server and user mapping properties.
*/
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 248aa73c0b..bb6b1a8fdf 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -6968,13 +6968,12 @@ select * from bar where f1 in (select f1 from foo) for update;
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- Async subplans: 1
- -> Async Foreign Scan on public.foo2
- Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
- Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-> Seq Scan on public.foo
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
-(29 rows)
+ -> Foreign Scan on public.foo2
+ Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
+ Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
+(23 rows)
select * from bar where f1 in (select f1 from foo) for update;
f1 | f2
@@ -7007,13 +7006,12 @@ select * from bar where f1 in (select f1 from foo) for share;
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- Async subplans: 1
- -> Async Foreign Scan on public.foo2
- Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
- Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-> Seq Scan on public.foo
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
-(29 rows)
+ -> Foreign Scan on public.foo2
+ Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
+ Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
+(23 rows)
select * from bar where f1 in (select f1 from foo) for share;
f1 | f2
@@ -7045,8 +7043,9 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- Async subplans: 1
- -> Async Foreign Scan on public.foo2
+ -> Seq Scan on public.foo
+ Output: foo.ctid, foo.*, foo.tableoid, foo.f1
+ -> Foreign Scan on public.foo2
Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-> Hash Join
@@ -7062,13 +7061,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
Group Key: foo.f1
-> Append
- Async subplans: 1
- -> Async Foreign Scan on public.foo2
- Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
- Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-> Seq Scan on public.foo
Output: foo.ctid, foo.*, foo.tableoid, foo.f1
-(41 rows)
+ -> Foreign Scan on public.foo2
+ Output: foo2.ctid, foo2.*, foo2.tableoid, foo2.f1
+ Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
+(39 rows)
update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
select tableoid::regclass, * from bar order by 1,2;
@@ -7098,11 +7096,14 @@ where bar.f1 = ss.f1;
Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1))
Hash Cond: (foo.f1 = bar.f1)
-> Append
- Async subplans: 2
- -> Async Foreign Scan on public.foo2
+ -> Seq Scan on public.foo
+ Output: ROW(foo.f1), foo.f1
+ -> Foreign Scan on public.foo2
Output: ROW(foo2.f1), foo2.f1
Remote SQL: SELECT f1 FROM public.loct1
- -> Async Foreign Scan on public.foo2 foo2_1
+ -> Seq Scan on public.foo foo_1
+ Output: ROW((foo_1.f1 + 3)), (foo_1.f1 + 3)
+ -> Foreign Scan on public.foo2 foo2_1
Output: ROW((foo2_1.f1 + 3)), (foo2_1.f1 + 3)
Remote SQL: SELECT f1 FROM public.loct1
-> Hash
@@ -7122,18 +7123,17 @@ where bar.f1 = ss.f1;
Output: (ROW(foo.f1)), foo.f1
Sort Key: foo.f1
-> Append
- Async subplans: 2
- -> Async Foreign Scan on public.foo2
- Output: ROW(foo2.f1), foo2.f1
- Remote SQL: SELECT f1 FROM public.loct1
- -> Async Foreign Scan on public.foo2 foo2_1
- Output: ROW((foo2_1.f1 + 3)), (foo2_1.f1 + 3)
- Remote SQL: SELECT f1 FROM public.loct1
-> Seq Scan on public.foo
Output: ROW(foo.f1), foo.f1
+ -> Foreign Scan on public.foo2
+ Output: ROW(foo2.f1), foo2.f1
+ Remote SQL: SELECT f1 FROM public.loct1
-> Seq Scan on public.foo foo_1
Output: ROW((foo_1.f1 + 3)), (foo_1.f1 + 3)
-(47 rows)
+ -> Foreign Scan on public.foo2 foo2_1
+ Output: ROW((foo2_1.f1 + 3)), (foo2_1.f1 + 3)
+ Remote SQL: SELECT f1 FROM public.loct1
+(45 rows)
update bar set f2 = f2 + 100
from
@@ -8155,12 +8155,11 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J
Sort
Sort Key: t1.a, t3.c
-> Append
- Async subplans: 2
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: ((public.ftprt1_p1 t1) INNER JOIN (public.ftprt2_p1 t2)) INNER JOIN (public.ftprt1_p1 t3)
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: ((public.ftprt1_p2 t1) INNER JOIN (public.ftprt2_p2 t2)) INNER JOIN (public.ftprt1_p2 t3)
-(8 rows)
+(7 rows)
SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE
t1.a% 25 =0 ORDER BY 1,2,3;
a | b | c
@@ -8179,10 +8178,9 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10)
Sort
Sort Key: t1.a, ftprt2_p1.b, ftprt2_p1.c
-> Append
- Async subplans: 1
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: (public.ftprt1_p1 t1) LEFT JOIN (public.ftprt2_p1 fprt2)
-(6 rows)
+(5 rows)
SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10) t2 ON (t1.a = t2.b and t1.b = t2.a)
WHEREt1.a < 10 ORDER BY 1,2,3;
a | b | c
@@ -8202,12 +8200,11 @@ SELECT t1,t2 FROM fprt1 t1 JOIN fprt2 t2 ON (t1.a = t2.b and t1.b = t2.a) WHERE
Sort
Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2)
-> Append
- Async subplans: 2
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: (public.ftprt1_p1 t1) INNER JOIN (public.ftprt2_p1 t2)
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: (public.ftprt1_p2 t1) INNER JOIN (public.ftprt2_p2 t2)
-(8 rows)
+(7 rows)
SELECT t1,t2 FROM fprt1 t1 JOIN fprt2 t2 ON (t1.a = t2.b and t1.b = t2.a) WHERE t1.a % 25 =0 ORDER BY 1,2;
t1 | t2
@@ -8226,12 +8223,11 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t
Sort
Sort Key: t1.a, t1.b
-> Append
- Async subplans: 2
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: (public.ftprt1_p1 t1) INNER JOIN (public.ftprt2_p1 t2)
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: (public.ftprt1_p2 t1) INNER JOIN (public.ftprt2_p2 t2)
-(8 rows)
+(7 rows)
SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE
t1.a%25= 0 ORDER BY 1,2;
a | b
@@ -8313,11 +8309,10 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O
Group Key: fpagg_tab_p1.a
Filter: (avg(fpagg_tab_p1.b) < '22'::numeric)
-> Append
- Async subplans: 3
- -> Async Foreign Scan on fpagg_tab_p1
- -> Async Foreign Scan on fpagg_tab_p2
- -> Async Foreign Scan on fpagg_tab_p3
-(10 rows)
+ -> Foreign Scan on fpagg_tab_p1
+ -> Foreign Scan on fpagg_tab_p2
+ -> Foreign Scan on fpagg_tab_p3
+(9 rows)
-- Plan with partitionwise aggregates is enabled
SET enable_partitionwise_aggregate TO true;
@@ -8328,14 +8323,13 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O
Sort
Sort Key: fpagg_tab_p1.a
-> Append
- Async subplans: 3
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: Aggregate on (public.fpagg_tab_p1 pagg_tab)
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: Aggregate on (public.fpagg_tab_p2 pagg_tab)
- -> Async Foreign Scan
+ -> Foreign Scan
Relations: Aggregate on (public.fpagg_tab_p3 pagg_tab)
-(10 rows)
+(9 rows)
SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1;
a | sum | min | count
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 78b0f43ca8..8efbbf95a8 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -20,6 +20,8 @@
#include "commands/defrem.h"
#include "commands/explain.h"
#include "commands/vacuum.h"
+#include "executor/execAsync.h"
+#include "executor/nodeForeignscan.h"
#include "foreign/fdwapi.h"
#include "funcapi.h"
#include "miscadmin.h"
@@ -34,6 +36,7 @@
#include "optimizer/var.h"
#include "optimizer/tlist.h"
#include "parser/parsetree.h"
+#include "pgstat.h"
#include "utils/builtins.h"
#include "utils/guc.h"
#include "utils/lsyscache.h"
@@ -53,6 +56,9 @@ PG_MODULE_MAGIC;
/* If no remote estimates, assume a sort costs 20% extra */
#define DEFAULT_FDW_SORT_MULTIPLIER 1.2
+/* Retrive PgFdwScanState struct from ForeginScanState */
+#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state)
+
/*
* Indexes of FDW-private information stored in fdw_private lists.
*
@@ -119,11 +125,28 @@ enum FdwDirectModifyPrivateIndex
FdwDirectModifyPrivateSetProcessed
};
+/*
+ * Connection private area structure.
+ */
+typedef struct PgFdwConnpriv
+{
+ ForeignScanState *leader; /* leader node of this connection */
+ bool busy; /* true if this connection is busy */
+} PgFdwConnpriv;
+
+/* Execution state base type */
+typedef struct PgFdwState
+{
+ PGconn *conn; /* connection for the scan */
+ PgFdwConnpriv *connpriv; /* connection private memory */
+} PgFdwState;
+
/*
* Execution state of a foreign scan using postgres_fdw.
*/
typedef struct PgFdwScanState
{
+ PgFdwState s; /* common structure */
Relation rel; /* relcache entry for the foreign table. NULL
* for a foreign join scan. */
TupleDesc tupdesc; /* tuple descriptor of scan */
@@ -134,7 +157,7 @@ typedef struct PgFdwScanState
List *retrieved_attrs; /* list of retrieved attribute numbers */
/* for remote query execution */
- PGconn *conn; /* connection for the scan */
+ bool result_ready;
unsigned int cursor_number; /* quasi-unique ID for my cursor */
bool cursor_exists; /* have we created the cursor? */
int numParams; /* number of parameters passed to query */
@@ -150,6 +173,12 @@ typedef struct PgFdwScanState
/* batch-level state, for optimizing rewinds and avoiding useless fetch */
int fetch_ct_2; /* Min(# of fetches done, 2) */
bool eof_reached; /* true if last fetch reached EOF */
+ bool run_async; /* true if run asynchronously */
+ bool inqueue; /* true if this node is in waiter queue */
+ ForeignScanState *waiter; /* Next node to run a query among nodes
+ * sharing the same connection */
+ ForeignScanState *last_waiter; /* last waiting node in waiting queue.
+ * valid only on the leader node */
/* working memory contexts */
MemoryContext batch_cxt; /* context holding current batch of tuples */
@@ -163,11 +192,11 @@ typedef struct PgFdwScanState
*/
typedef struct PgFdwModifyState
{
+ PgFdwState s; /* common structure */
Relation rel; /* relcache entry for the foreign table */
AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
/* for remote query execution */
- PGconn *conn; /* connection for the scan */
char *p_name; /* name of prepared statement, if created */
/* extracted fdw_private data */
@@ -190,6 +219,7 @@ typedef struct PgFdwModifyState
*/
typedef struct PgFdwDirectModifyState
{
+ PgFdwState s; /* common structure */
Relation rel; /* relcache entry for the foreign table */
AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
@@ -293,6 +323,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags);
static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node);
static void postgresReScanForeignScan(ForeignScanState *node);
static void postgresEndForeignScan(ForeignScanState *node);
+static void postgresShutdownForeignScan(ForeignScanState *node);
static void postgresAddForeignUpdateTargets(Query *parsetree,
RangeTblEntry *target_rte,
Relation target_relation);
@@ -358,6 +389,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root,
RelOptInfo *input_rel,
RelOptInfo *output_rel,
void *extra);
+static bool postgresIsForeignPathAsyncCapable(ForeignPath *path);
+static bool postgresForeignAsyncConfigureWait(ForeignScanState *node,
+ WaitEventSet *wes,
+ void *caller_data, bool reinit);
/*
* Helper functions
@@ -378,7 +413,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel,
EquivalenceClass *ec, EquivalenceMember *em,
void *arg);
static void create_cursor(ForeignScanState *node);
-static void fetch_more_data(ForeignScanState *node);
+static void request_more_data(ForeignScanState *node);
+static void fetch_received_data(ForeignScanState *node);
+static void vacate_connection(PgFdwState *fdwconn, bool clear_queue);
static void close_cursor(PGconn *conn, unsigned int cursor_number);
static PgFdwModifyState *create_foreign_modify(EState *estate,
RangeTblEntry *rte,
@@ -469,6 +506,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS)
routine->IterateForeignScan = postgresIterateForeignScan;
routine->ReScanForeignScan = postgresReScanForeignScan;
routine->EndForeignScan = postgresEndForeignScan;
+ routine->ShutdownForeignScan = postgresShutdownForeignScan;
/* Functions for updating foreign tables */
routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets;
@@ -505,6 +543,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS)
/* Support functions for upper relation push-down */
routine->GetForeignUpperPaths = postgresGetForeignUpperPaths;
+ /* Support functions for async execution */
+ routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable;
+ routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait;
+
PG_RETURN_POINTER(routine);
}
@@ -1355,12 +1397,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags)
* Get connection to the foreign server. Connection manager will
* establish new connection if necessary.
*/
- fsstate->conn = GetConnection(user, false);
+ fsstate->s.conn = GetConnection(user, false);
+ fsstate->s.connpriv = (PgFdwConnpriv *)
+ GetConnectionSpecificStorage(user, sizeof(PgFdwConnpriv));
+ fsstate->s.connpriv->leader = NULL;
+ fsstate->s.connpriv->busy = false;
+ fsstate->waiter = NULL;
+ fsstate->last_waiter = node;
/* Assign a unique ID for my cursor */
- fsstate->cursor_number = GetCursorNumber(fsstate->conn);
+ fsstate->cursor_number = GetCursorNumber(fsstate->s.conn);
fsstate->cursor_exists = false;
+ /* Initialize async execution status */
+ fsstate->run_async = false;
+ fsstate->inqueue = false;
+
/* Get private info created by planner functions. */
fsstate->query = strVal(list_nth(fsplan->fdw_private,
FdwScanPrivateSelectSql));
@@ -1408,40 +1460,250 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags)
&fsstate->param_values);
}
+/*
+ * Async queue manipuration functions
+ */
+
+/*
+ * add_async_waiter:
+ *
+ * adds the node to the end of waiter queue
+ */
+static inline void
+add_async_waiter(ForeignScanState *node)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+ ForeignScanState *leader = fsstate->s.connpriv->leader;
+ PgFdwScanState *leader_state;
+ PgFdwScanState *last_waiter_state;
+
+ Assert(leader && leader != node);
+
+ /* do nothing if the node is already in the queue */
+ if (fsstate->inqueue)
+ return;
+
+ leader_state = GetPgFdwScanState(leader);
+ last_waiter_state = GetPgFdwScanState(leader_state->last_waiter);
+ last_waiter_state->waiter = node;
+ leader_state->last_waiter = node;
+ fsstate->inqueue = true;
+}
+
+/*
+ * move_to_next_waiter:
+ *
+ * Makes the first waiter be next leader
+ * Returns the new leader or NULL if there's no waiter.
+ */
+static inline ForeignScanState *
+move_to_next_waiter(ForeignScanState *node)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+ ForeignScanState *ret = fsstate->waiter;
+
+ Assert(fsstate->s.connpriv->leader = node);
+
+ if (ret)
+ {
+ PgFdwScanState *retstate = GetPgFdwScanState(ret);
+ fsstate->waiter = NULL;
+ retstate->last_waiter = fsstate->last_waiter;
+ retstate->inqueue = false;
+ }
+
+ fsstate->s.connpriv->leader = ret;
+
+ return ret;
+}
+
+/*
+ * remove the node from waiter queue
+ *
+ * This is a bit different from the two above in the sense that this can
+ * operate on connection leader. The result is absorbed when this is called on
+ * active leader.
+ *
+ * Returns true if the node was found.
+ */
+static inline bool
+remove_async_node(ForeignScanState *node)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+ ForeignScanState *leader = fsstate->s.connpriv->leader;
+ PgFdwScanState *leader_state;
+ ForeignScanState *prev;
+ PgFdwScanState *prev_state;
+ ForeignScanState *cur;
+
+ /* no need to remove me */
+ if (!leader || !fsstate->inqueue)
+ return false;
+
+ leader_state = GetPgFdwScanState(leader);
+
+ /* Remove the leader node */
+ if (leader == node)
+ {
+ ForeignScanState *next_leader;
+
+ if (leader_state->s.connpriv->busy)
+ {
+ /*
+ * this node is waiting for result, absorb the result first so
+ * that the following commands can be sent on the connection.
+ */
+ PgFdwScanState *leader_state = GetPgFdwScanState(leader);
+ PGconn *conn = leader_state->s.conn;
+
+ while(PQisBusy(conn))
+ PQclear(PQgetResult(conn));
+
+ leader_state->s.connpriv->busy = false;
+ }
+
+ /* Make the first waiter the leader */
+ if (leader_state->waiter)
+ {
+ PgFdwScanState *next_leader_state;
+
+ next_leader = leader_state->waiter;
+ next_leader_state = GetPgFdwScanState(next_leader);
+
+ leader_state->s.connpriv->leader = next_leader;
+ next_leader_state->last_waiter = leader_state->last_waiter;
+ }
+ leader_state->waiter = NULL;
+
+ return true;
+ }
+
+ /*
+ * Just remove the node in queue
+ *
+ * This function is called on the shutdown path. We don't bother
+ * considering faster way to do this.
+ */
+ prev = leader;
+ prev_state = leader_state;
+ cur = GetPgFdwScanState(prev)->waiter;
+ while (cur)
+ {
+ PgFdwScanState *curstate = GetPgFdwScanState(cur);
+
+ if (cur == node)
+ {
+ prev_state->waiter = curstate->waiter;
+ if (leader_state->last_waiter == cur)
+ leader_state->last_waiter = prev;
+ else
+ leader_state->last_waiter = cur;
+
+ fsstate->inqueue = false;
+
+ return true;
+ }
+ prev = cur;
+ prev_state = curstate;
+ cur = curstate->waiter;
+ }
+
+ return false;
+}
+
/*
* postgresIterateForeignScan
- * Retrieve next row from the result set, or clear tuple slot to indicate
- * EOF.
+ * Retrieve next row from the result set.
+ *
+ * For synchronous nodes, returns clear tuples slot to indicte EOF.
+ *
+ * If the node is asynchronous one, clear tuple slot has two meanings.
+ * If the caller receives clear tuple slot, asyncstate indicates wheter
+ * the node is EOF (AS_AVAILABLE) or waiting for data to
+ * come(AS_WAITING).
*/
static TupleTableSlot *
postgresIterateForeignScan(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
TupleTableSlot *slot = node->ss.ss_ScanTupleSlot;
- /*
- * If this is the first call after Begin or ReScan, we need to create the
- * cursor on the remote side.
- */
- if (!fsstate->cursor_exists)
- create_cursor(node);
+ if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached)
+ {
+ /* we've run out, get some more tuples */
+ if (!node->fs_async)
+ {
+ /* finish running query to send my command */
+ if (!fsstate->s.connpriv->busy)
+ vacate_connection((PgFdwState *)fsstate, false);
+
+ request_more_data(node);
+
+ /*
+ * Fetch the result immediately. This executes the next waiter if
+ * any.
+ */
+ fetch_received_data(node);
+ }
+ else if (!fsstate->s.connpriv->busy)
+ {
+ /* If the connection is not busy, just send the request. */
+ request_more_data(node);
+ }
+ else if (fsstate->s.connpriv->leader == node)
+ {
+ bool available = true;
+
+ /* Check if the result is available */
+ if (PQisBusy(fsstate->s.conn))
+ {
+ int rc = WaitLatchOrSocket(NULL,
+ WL_SOCKET_READABLE | WL_TIMEOUT,
+ PQsocket(fsstate->s.conn), 0,
+ WAIT_EVENT_ASYNC_WAIT);
+ if (!(rc & WL_SOCKET_READABLE))
+ available = false;
+ }
+
+ /* The next waiter is executed automatcically */
+ if (available)
+ fetch_received_data(node);
+ }
+ else if (fsstate->s.connpriv->leader)
+ {
+ /*
+ * Anyone else is waiting on this connection then add this node to
+ * waiting queue.
+ */
+ add_async_waiter(node);
+ }
+ }
/*
- * Get some more tuples, if we've run out.
+ * If we haven't received a result for the given node this time,
+ * return with no tuple to give way to another node.
*/
if (fsstate->next_tuple >= fsstate->num_tuples)
{
- /* No point in another fetch if we already detected EOF, though. */
- if (!fsstate->eof_reached)
- fetch_more_data(node);
- /* If we didn't get any tuples, must be end of data. */
- if (fsstate->next_tuple >= fsstate->num_tuples)
- return ExecClearTuple(slot);
+ if (fsstate->eof_reached)
+ {
+ fsstate->result_ready = true;
+ node->ss.ps.asyncstate = AS_AVAILABLE;
+ }
+ else
+ {
+ fsstate->result_ready = false;
+ node->ss.ps.asyncstate = AS_WAITING;
+ }
+
+ return ExecClearTuple(slot);
}
/*
* Return the next tuple.
*/
+ fsstate->result_ready = true;
+ node->ss.ps.asyncstate = AS_AVAILABLE;
ExecStoreTuple(fsstate->tuples[fsstate->next_tuple++],
slot,
InvalidBuffer,
@@ -1457,7 +1719,7 @@ postgresIterateForeignScan(ForeignScanState *node)
static void
postgresReScanForeignScan(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
char sql[64];
PGresult *res;
@@ -1465,6 +1727,8 @@ postgresReScanForeignScan(ForeignScanState *node)
if (!fsstate->cursor_exists)
return;
+ vacate_connection((PgFdwState *)fsstate, true);
+
/*
* If any internal parameters affecting this node have changed, we'd
* better destroy and recreate the cursor. Otherwise, rewinding it should
@@ -1493,9 +1757,9 @@ postgresReScanForeignScan(ForeignScanState *node)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_exec_query(fsstate->conn, sql);
+ res = pgfdw_exec_query(fsstate->s.conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, fsstate->conn, true, sql);
+ pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql);
PQclear(res);
/* Now force a fresh FETCH. */
@@ -1513,7 +1777,7 @@ postgresReScanForeignScan(ForeignScanState *node)
static void
postgresEndForeignScan(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
/* if fsstate is NULL, we are in EXPLAIN; nothing to do */
if (fsstate == NULL)
@@ -1521,15 +1785,31 @@ postgresEndForeignScan(ForeignScanState *node)
/* Close the cursor if open, to prevent accumulation of cursors */
if (fsstate->cursor_exists)
- close_cursor(fsstate->conn, fsstate->cursor_number);
+ close_cursor(fsstate->s.conn, fsstate->cursor_number);
/* Release remote connection */
- ReleaseConnection(fsstate->conn);
- fsstate->conn = NULL;
+ ReleaseConnection(fsstate->s.conn);
+ fsstate->s.conn = NULL;
/* MemoryContexts will be deleted automatically. */
}
+/*
+ * postgresShutdownForeignScan
+ * Remove asynchrony stuff and cleanup garbage on the connection.
+ */
+static void
+postgresShutdownForeignScan(ForeignScanState *node)
+{
+ ForeignScan *plan = (ForeignScan *) node->ss.ps.plan;
+
+ if (plan->operation != CMD_SELECT)
+ return;
+
+ /* remove the node from waiting queue */
+ remove_async_node(node);
+}
+
/*
* postgresAddForeignUpdateTargets
* Add resjunk column(s) needed for update/delete on a foreign table
@@ -1753,6 +2033,9 @@ postgresExecForeignInsert(EState *estate,
PGresult *res;
int n_rows;
+ /* finish running query to send my command */
+ vacate_connection((PgFdwState *)fmstate, true);
+
/* Set up the prepared statement on the remote server, if we didn't yet */
if (!fmstate->p_name)
prepare_foreign_modify(fmstate);
@@ -1763,14 +2046,14 @@ postgresExecForeignInsert(EState *estate,
/*
* Execute the prepared statement.
*/
- if (!PQsendQueryPrepared(fmstate->conn,
+ if (!PQsendQueryPrepared(fmstate->s.conn,
fmstate->p_name,
fmstate->p_nums,
p_values,
NULL,
NULL,
0))
- pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+ pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query);
/*
* Get the result, and check for success.
@@ -1778,10 +2061,10 @@ postgresExecForeignInsert(EState *estate,
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_get_result(fmstate->conn, fmstate->query);
+ res = pgfdw_get_result(fmstate->s.conn, fmstate->query);
if (PQresultStatus(res) !=
(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query);
/* Check number of rows affected, and fetch RETURNING tuple if any */
if (fmstate->has_returning)
@@ -1819,6 +2102,9 @@ postgresExecForeignUpdate(EState *estate,
PGresult *res;
int n_rows;
+ /* finish running query to send my command */
+ vacate_connection((PgFdwState *)fmstate, true);
+
/* Set up the prepared statement on the remote server, if we didn't yet */
if (!fmstate->p_name)
prepare_foreign_modify(fmstate);
@@ -1839,14 +2125,14 @@ postgresExecForeignUpdate(EState *estate,
/*
* Execute the prepared statement.
*/
- if (!PQsendQueryPrepared(fmstate->conn,
+ if (!PQsendQueryPrepared(fmstate->s.conn,
fmstate->p_name,
fmstate->p_nums,
p_values,
NULL,
NULL,
0))
- pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+ pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query);
/*
* Get the result, and check for success.
@@ -1854,10 +2140,10 @@ postgresExecForeignUpdate(EState *estate,
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_get_result(fmstate->conn, fmstate->query);
+ res = pgfdw_get_result(fmstate->s.conn, fmstate->query);
if (PQresultStatus(res) !=
(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query);
/* Check number of rows affected, and fetch RETURNING tuple if any */
if (fmstate->has_returning)
@@ -1895,6 +2181,9 @@ postgresExecForeignDelete(EState *estate,
PGresult *res;
int n_rows;
+ /* finish running query to send my command */
+ vacate_connection((PgFdwState *)fmstate, true);
+
/* Set up the prepared statement on the remote server, if we didn't yet */
if (!fmstate->p_name)
prepare_foreign_modify(fmstate);
@@ -1915,14 +2204,14 @@ postgresExecForeignDelete(EState *estate,
/*
* Execute the prepared statement.
*/
- if (!PQsendQueryPrepared(fmstate->conn,
+ if (!PQsendQueryPrepared(fmstate->s.conn,
fmstate->p_name,
fmstate->p_nums,
p_values,
NULL,
NULL,
0))
- pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+ pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query);
/*
* Get the result, and check for success.
@@ -1930,10 +2219,10 @@ postgresExecForeignDelete(EState *estate,
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_get_result(fmstate->conn, fmstate->query);
+ res = pgfdw_get_result(fmstate->s.conn, fmstate->query);
if (PQresultStatus(res) !=
(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query);
/* Check number of rows affected, and fetch RETURNING tuple if any */
if (fmstate->has_returning)
@@ -2400,7 +2689,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags)
* Get connection to the foreign server. Connection manager will
* establish new connection if necessary.
*/
- dmstate->conn = GetConnection(user, false);
+ dmstate->s.conn = GetConnection(user, false);
+ dmstate->s.connpriv = (PgFdwConnpriv *)
+ GetConnectionSpecificStorage(user, sizeof(PgFdwConnpriv));
/* Update the foreign-join-related fields. */
if (fsplan->scan.scanrelid == 0)
@@ -2485,7 +2776,11 @@ postgresIterateDirectModify(ForeignScanState *node)
* If this is the first call after Begin, execute the statement.
*/
if (dmstate->num_tuples == -1)
+ {
+ /* finish running query to send my command */
+ vacate_connection((PgFdwState *)dmstate, true);
execute_dml_stmt(node);
+ }
/*
* If the local query doesn't specify RETURNING, just clear tuple slot.
@@ -2532,8 +2827,8 @@ postgresEndDirectModify(ForeignScanState *node)
PQclear(dmstate->result);
/* Release remote connection */
- ReleaseConnection(dmstate->conn);
- dmstate->conn = NULL;
+ ReleaseConnection(dmstate->s.conn);
+ dmstate->s.conn = NULL;
/* close the target relation. */
if (dmstate->resultRel)
@@ -2656,6 +2951,7 @@ estimate_path_cost_size(PlannerInfo *root,
List *local_param_join_conds;
StringInfoData sql;
PGconn *conn;
+ PgFdwConnpriv *connpriv;
Selectivity local_sel;
QualCost local_cost;
List *fdw_scan_tlist = NIL;
@@ -2698,6 +2994,18 @@ estimate_path_cost_size(PlannerInfo *root,
/* Get the remote estimate */
conn = GetConnection(fpinfo->user, false);
+ connpriv = GetConnectionSpecificStorage(fpinfo->user,
+ sizeof(PgFdwConnpriv));
+ if (connpriv)
+ {
+ PgFdwState tmpstate;
+ tmpstate.conn = conn;
+ tmpstate.connpriv = connpriv;
+
+ /* finish running query to send my command */
+ vacate_connection(&tmpstate, true);
+ }
+
get_remote_estimate(sql.data, conn, &rows, &width,
&startup_cost, &total_cost);
ReleaseConnection(conn);
@@ -3061,11 +3369,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel,
static void
create_cursor(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
ExprContext *econtext = node->ss.ps.ps_ExprContext;
int numParams = fsstate->numParams;
const char **values = fsstate->param_values;
- PGconn *conn = fsstate->conn;
+ PGconn *conn = fsstate->s.conn;
StringInfoData buf;
PGresult *res;
@@ -3128,50 +3436,121 @@ create_cursor(ForeignScanState *node)
}
/*
- * Fetch some more rows from the node's cursor.
+ * Sends the next request of the node. If the given node is different from the
+ * current connection leader, pushes it back to waiter queue and let the given
+ * node be the leader.
*/
static void
-fetch_more_data(ForeignScanState *node)
+request_more_data(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+ ForeignScanState *leader = fsstate->s.connpriv->leader;
+ PGconn *conn = fsstate->s.conn;
+ char sql[64];
+
+ /* must be non-busy */
+ Assert(!fsstate->s.connpriv->busy);
+ /* must be not-eof */
+ Assert(!fsstate->eof_reached);
+
+ /*
+ * If this is the first call after Begin or ReScan, we need to create the
+ * cursor on the remote side.
+ */
+ if (!fsstate->cursor_exists)
+ create_cursor(node);
+
+ snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
+ fsstate->fetch_size, fsstate->cursor_number);
+
+ if (!PQsendQuery(conn, sql))
+ pgfdw_report_error(ERROR, NULL, conn, false, sql);
+
+ fsstate->s.connpriv->busy = true;
+
+ /* Let the node be the leader if it is different from current one */
+ if (leader != node)
+ {
+ /*
+ * If the connection leader exists, insert the node as the connection
+ * leader making the current leader be the first waiter.
+ */
+ if (leader != NULL)
+ {
+ remove_async_node(node);
+ fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter;
+ fsstate->waiter = leader;
+ }
+ fsstate->s.connpriv->leader = node;
+ }
+}
+
+/*
+ * Fetches received data and automatically send requests of the next waiter.
+ */
+static void
+fetch_received_data(ForeignScanState *node)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
PGresult *volatile res = NULL;
MemoryContext oldcontext;
+ ForeignScanState *waiter;
+
+ /* I should be the current connection leader */
+ Assert(fsstate->s.connpriv->leader == node);
/*
* We'll store the tuples in the batch_cxt. First, flush the previous
- * batch.
+ * batch if no tuple is remaining
*/
- fsstate->tuples = NULL;
- MemoryContextReset(fsstate->batch_cxt);
+ if (fsstate->next_tuple >= fsstate->num_tuples)
+ {
+ fsstate->tuples = NULL;
+ fsstate->num_tuples = 0;
+ MemoryContextReset(fsstate->batch_cxt);
+ }
+ else if (fsstate->next_tuple > 0)
+ {
+ /* move the remaining tuples to the beginning of the store */
+ int n = 0;
+
+ while(fsstate->next_tuple < fsstate->num_tuples)
+ fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++];
+ fsstate->num_tuples = n;
+ }
+
oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt);
/* PGresult must be released before leaving this function. */
PG_TRY();
{
- PGconn *conn = fsstate->conn;
+ PGconn *conn = fsstate->s.conn;
char sql[64];
- int numrows;
+ int addrows;
+ size_t newsize;
int i;
snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
fsstate->fetch_size, fsstate->cursor_number);
- res = pgfdw_exec_query(conn, sql);
+ res = pgfdw_get_result(conn, sql);
/* On error, report the original query, not the FETCH. */
if (PQresultStatus(res) != PGRES_TUPLES_OK)
pgfdw_report_error(ERROR, res, conn, false, fsstate->query);
/* Convert the data into HeapTuples */
- numrows = PQntuples(res);
- fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple));
- fsstate->num_tuples = numrows;
- fsstate->next_tuple = 0;
+ addrows = PQntuples(res);
+ newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple);
+ if (fsstate->tuples)
+ fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize);
+ else
+ fsstate->tuples = (HeapTuple *) palloc(newsize);
- for (i = 0; i < numrows; i++)
+ for (i = 0; i < addrows; i++)
{
Assert(IsA(node->ss.ps.plan, ForeignScan));
- fsstate->tuples[i] =
+ fsstate->tuples[fsstate->num_tuples + i] =
make_tuple_from_result_row(res, i,
fsstate->rel,
fsstate->attinmeta,
@@ -3181,26 +3560,76 @@ fetch_more_data(ForeignScanState *node)
}
/* Update fetch_ct_2 */
- if (fsstate->fetch_ct_2 < 2)
+ if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0)
fsstate->fetch_ct_2++;
+ fsstate->next_tuple = 0;
+ fsstate->num_tuples += addrows;
+
/* Must be EOF if we didn't get as many tuples as we asked for. */
- fsstate->eof_reached = (numrows < fsstate->fetch_size);
+ fsstate->eof_reached = (addrows < fsstate->fetch_size);
PQclear(res);
res = NULL;
}
PG_CATCH();
{
+ fsstate->s.connpriv->busy = false;
+
if (res)
PQclear(res);
PG_RE_THROW();
}
PG_END_TRY();
+ fsstate->s.connpriv->busy = false;
+
+ /* let the first waiter be the next leader of this connection */
+ waiter = move_to_next_waiter(node);
+
+ /* send the next request if any */
+ if (waiter)
+ request_more_data(waiter);
+
MemoryContextSwitchTo(oldcontext);
}
+/*
+ * Vacate a connection so that this node can send the next query
+ */
+static void
+vacate_connection(PgFdwState *fdwstate, bool clear_queue)
+{
+ PgFdwConnpriv *connpriv = fdwstate->connpriv;
+ ForeignScanState *leader;
+
+ /* the connection is alrady available */
+ if (connpriv == NULL || connpriv->leader == NULL || !connpriv->busy)
+ return;
+
+ /*
+ * let the current connection leader read the result for the running query
+ */
+ leader = connpriv->leader;
+ fetch_received_data(leader);
+
+ /* let the first waiter be the next leader of this connection */
+ move_to_next_waiter(leader);
+
+ if (!clear_queue)
+ return;
+
+ /* Clear the waiting list */
+ while (leader)
+ {
+ PgFdwScanState *fsstate = GetPgFdwScanState(leader);
+
+ fsstate->last_waiter = NULL;
+ leader = fsstate->waiter;
+ fsstate->waiter = NULL;
+ }
+}
+
/*
* Force assorted GUC parameters to settings that ensure that we'll output
* data values in a form that is unambiguous to the remote server.
@@ -3314,7 +3743,9 @@ create_foreign_modify(EState *estate,
user = GetUserMapping(userid, table->serverid);
/* Open connection; report that we'll create a prepared statement. */
- fmstate->conn = GetConnection(user, true);
+ fmstate->s.conn = GetConnection(user, true);
+ fmstate->s.connpriv = (PgFdwConnpriv *)
+ GetConnectionSpecificStorage(user, sizeof(PgFdwConnpriv));
fmstate->p_name = NULL; /* prepared statement not made yet */
/* Set up remote query information. */
@@ -3387,7 +3818,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
/* Construct name we'll use for the prepared statement. */
snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u",
- GetPrepStmtNumber(fmstate->conn));
+ GetPrepStmtNumber(fmstate->s.conn));
p_name = pstrdup(prep_name);
/*
@@ -3397,12 +3828,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
* the prepared statements we use in this module are simple enough that
* the remote server will make the right choices.
*/
- if (!PQsendPrepare(fmstate->conn,
+ if (!PQsendPrepare(fmstate->s.conn,
p_name,
fmstate->query,
0,
NULL))
- pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+ pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query);
/*
* Get the result, and check for success.
@@ -3410,9 +3841,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_get_result(fmstate->conn, fmstate->query);
+ res = pgfdw_get_result(fmstate->s.conn, fmstate->query);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query);
PQclear(res);
/* This action shows that the prepare has been done. */
@@ -3537,16 +3968,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_exec_query(fmstate->conn, sql);
+ res = pgfdw_exec_query(fmstate->s.conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, fmstate->conn, true, sql);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql);
PQclear(res);
fmstate->p_name = NULL;
}
/* Release remote connection */
- ReleaseConnection(fmstate->conn);
- fmstate->conn = NULL;
+ ReleaseConnection(fmstate->s.conn);
+ fmstate->s.conn = NULL;
}
/*
@@ -3706,9 +4137,9 @@ execute_dml_stmt(ForeignScanState *node)
* the desired result. This allows us to avoid assuming that the remote
* server has the same OIDs we do for the parameters' types.
*/
- if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams,
+ if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams,
NULL, values, NULL, NULL, 0))
- pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query);
+ pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query);
/*
* Get the result, and check for success.
@@ -3716,10 +4147,10 @@ execute_dml_stmt(ForeignScanState *node)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query);
+ dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query);
if (PQresultStatus(dmstate->result) !=
(dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true,
+ pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true,
dmstate->query);
/* Get the number of rows affected. */
@@ -5203,6 +5634,42 @@ postgresGetForeignJoinPaths(PlannerInfo *root,
/* XXX Consider parameterized paths for the join relation */
}
+static bool
+postgresIsForeignPathAsyncCapable(ForeignPath *path)
+{
+ return true;
+}
+
+
+/*
+ * Configure waiting event.
+ *
+ * Add an wait event only when the node is the connection leader. Elsewise
+ * another node on this connection is the leader.
+ */
+static bool
+postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes,
+ void *caller_data, bool reinit)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+
+
+ /* If the caller didn't reinit, this event is already in event set */
+ if (!reinit)
+ return true;
+
+ if (fsstate->s.connpriv->leader == node)
+ {
+ AddWaitEventToSet(wes,
+ WL_SOCKET_READABLE, PQsocket(fsstate->s.conn),
+ NULL, caller_data);
+ return true;
+ }
+
+ return false;
+}
+
+
/*
* Assess whether the aggregation, grouping and having operations can be pushed
* down to the foreign server. As a side effect, save information we obtain in
diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h
index a5d4011e8d..f344fb7f66 100644
--- a/contrib/postgres_fdw/postgres_fdw.h
+++ b/contrib/postgres_fdw/postgres_fdw.h
@@ -77,6 +77,7 @@ typedef struct PgFdwRelationInfo
UserMapping *user; /* only set in use_remote_estimate mode */
int fetch_size; /* fetch size for this remote table */
+ bool allow_prefetch; /* true to allow overlapped fetching */
/*
* Name of the relation while EXPLAINing ForeignScan. It is used for join
@@ -116,6 +117,7 @@ extern void reset_transmission_modes(int nestlevel);
/* in connection.c */
extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt);
+void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize);
extern void ReleaseConnection(PGconn *conn);
extern unsigned int GetCursorNumber(PGconn *conn);
extern unsigned int GetPrepStmtNumber(PGconn *conn);
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index 231b1e01a5..8ecc903c20 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -1617,25 +1617,25 @@ INSERT INTO b(aa) VALUES('bbb');
INSERT INTO b(aa) VALUES('bbbb');
INSERT INTO b(aa) VALUES('bbbbb');
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
UPDATE b SET aa = 'new';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
UPDATE a SET aa = 'newtoo';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
@@ -1677,12 +1677,12 @@ insert into bar2 values(4,44,44);
insert into bar2 values(7,77,77);
explain (verbose, costs off)
-select * from bar where f1 in (select f1 from foo) for update;
-select * from bar where f1 in (select f1 from foo) for update;
+select * from bar where f1 in (select f1 from foo) order by 1 for update;
+select * from bar where f1 in (select f1 from foo) order by 1 for update;
explain (verbose, costs off)
-select * from bar where f1 in (select f1 from foo) for share;
-select * from bar where f1 in (select f1 from foo) for share;
+select * from bar where f1 in (select f1 from foo) order by 1 for share;
+select * from bar where f1 in (select f1 from foo) order by 1 for share;
-- Check UPDATE with inherited target and an inherited source table
explain (verbose, costs off)
@@ -1741,8 +1741,8 @@ explain (verbose, costs off)
delete from foo where f1 < 5 returning *;
delete from foo where f1 < 5 returning *;
explain (verbose, costs off)
-update bar set f2 = f2 + 100 returning *;
-update bar set f2 = f2 + 100 returning *;
+with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1;
+with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1;
-- Test that UPDATE/DELETE with inherited target works with row-level triggers
CREATE TRIGGER trig_row_before
--
2.16.3
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