Postgres Pro
Downloads
Home   >   mailing lists

Thread: 7.4 beta 1 getting out of swap

7.4 beta 1 getting out of swap

From
Bertrand Petit
Date:
    Hello,

    I recently switched to 7.4 beta 1, one query that used to be
corectly executed uder 7.3.3 albeit slowly now abnormaly ends when the
backend can't get more memory when it ate about 480 MB of swap space.
I suspect that this behavior is the result of a 7.4 beta 1 bug but I
wanted to be sure it is one before posting a report on pgsql-bugs.

    That query operates on three tables:

==============================================================================
db=> \d movies
                              Table "public.movies"
   Column   |       Type        |                    Modifiers
------------+-------------------+-------------------------------------------------
 id         | bigint            | not null default nextval('movies_id_seq'::text)
 title      | character varying | not null
 orig_title | character varying | not null
 year       | smallint          |
 year_end   | smallint          |
Indexes:
    "movies_id_idx" unique, btree (id)
    "movies_title_idx" unique, btree (title)
    "movies_orig_title_idx" btree (orig_title)
    "movies_year_idx" btree ("year")
Check constraints:
    "movies_year" CHECK (("year" >= 1888) OR ("year" IS NULL))
    "$1" CHECK ((year_end >= 1888) OR (year_end IS NULL))

db=> \d raw_atitles
                            Table "public.raw_atitles"
   Column   |        Type         |                    Modifiers
------------+---------------------+--------------------------------------------------
 main_title | character varying   | not null
 aka_title  | character varying   |
 charset    | character varying   | not null default 'ISO-8859-1'::character varying
 byte_title | character varying   | not null
 attribs    | character varying[] |
Indexes:
    "rimdb_atitles_aka_title_idx" btree (aka_title)
    "rimdb_atitles_attribs_idx" btree (attribs array_ops)
    "rimdb_atitles_main_title_idx" btree (main_title)

db=> \d atitles
            Table "public.atitles"
   Column   |        Type         | Modifiers
------------+---------------------+-----------
 title      | character varying   | not null
 movie_id   | bigint              | not null
 attribs    | character varying[] |
 orig_title | character varying   | not null
Indexes:
    "truc" unique, btree (movie_id, orig_title, attribs array_ops)
    "atitles_movie_id_idx" btree (movie_id)
    "atitles_title_idx" btree (title)
Foreign-key constraints:
    "$1" FOREIGN KEY (movie_id) REFERENCES movies(id)

==============================================================================

    The operation is to update the "core" atitles table with the
contents of the "raw" raw_atitles table. The query is as follows:

==============================================================================
INSERT INTO atitles (movie_id, title, attribs, orig_title)
  SELECT mo.id, trans_title(rak.aka_title), rak.attribs, rak.aka_title
  FROM movies AS mo, raw_atitles AS rak
  WHERE mo.orig_title=rak.main_title AND
  NOT EXISTS
    (SELECT at2.movie_id from atitles AS at2
     WHERE at2.movie_id=mo.id AND
     at2.orig_title=rak.aka_title AND
     at2.attribs=rak.attribs);
==============================================================================

    Table sizes are 362,921 rows for movies, 152,549 for atitles,
and 160,114 for raw_atitles.

    The query plan is:

==============================================================================
                                            QUERY PLAN
--------------------------------------------------------------------------------------------------
 Merge Join  (cost=106998.67..1039376.63 rows=80057 width=86)
   Merge Cond: ("outer"."?column3?" = "inner"."?column4?")
   Join Filter: (NOT (subplan))
   ->  Sort  (cost=66212.69..67119.99 rows=362921 width=38)
         Sort Key: (mo.orig_title)::text
         ->  Seq Scan on movies mo  (cost=0.00..8338.21 rows=362921 width=38)
   ->  Sort  (cost=40785.99..41186.27 rows=160114 width=107)
         Sort Key: (rak.main_title)::text
         ->  Seq Scan on raw_atitles rak  (cost=0.00..5145.14 rows=160114 width=107)
   SubPlan
     ->  Index Scan using truc on atitles at2  (cost=0.00..5.80 rows=1 width=8)
           Index Cond: ((movie_id = $0) AND ((orig_title)::text = ($1)::text) AND (attribs = $2))
(12 rows)

==============================================================================

    I suspect that the backend does not comply to the sort_mem
parameter (set to the default 1024).

    So my question is: does this really looks like a bug?

    Regards.

--
%!PS
297.6 420.9 translate 90 rotate 0 setgray gsave 0 1 1{pop 0 180 moveto 100
180 170 100 170 -10 curveto 180 -9 180 -9 190 -10 curveto 190 100 100 180
0 180 curveto fill 180 rotate}for grestore/Bookman-LightItalic findfont
240 scalefont setfont -151.536392 -63.7998886 moveto (bp)show showpage

Re: 7.4 beta 1 getting out of swap

From
Tom Lane
Date:
Bertrand Petit <pgsql@phoe.frmug.org> writes:
>     I recently switched to 7.4 beta 1, one query that used to be
> corectly executed uder 7.3.3 albeit slowly now abnormaly ends when the
> backend can't get more memory when it ate about 480 MB of swap space.

Please show us the memory context size info that the backend dumps to
stderr when it reports "out of memory".

            regards, tom lane

Re: 7.4 beta 1 getting out of swap

From
Tom Lane
Date:
Bertrand Petit <pgsql@phoe.frmug.org> writes:
> On Thu, Aug 14, 2003 at 07:45:46AM -0400, Tom Lane wrote:
>> Please show us the memory context size info that the backend dumps to
>> stderr when it reports "out of memory".

>     Here it is:

> ExecutorState: 4556232 total in 46 blocks; 3183264 free (8303 chunks); 1372968 used

That seems a bit large, but I'm not sure if it's really to worry about.

> ExecutorState: 528474112 total in 72 blocks; 760 free (1 chunks); 528473352 used

Okay, you definitely must have a memory leak in query execution.

Could you provide enough info to let someone else reproduce it?  We
don't need your data, but a schema dump (pg_dump -s) would be nice
to avoid trying to guess what causes it.

            regards, tom lane

Re: 7.4 beta 1 getting out of swap

From
Bertrand Petit
Date:
On Thu, Aug 14, 2003 at 07:45:46AM -0400, Tom Lane wrote:
>
> Please show us the memory context size info that the backend dumps to
> stderr when it reports "out of memory".

    Here it is:

==============================================================================
TopMemoryContext: 32792 total in 4 blocks; 14600 free (9 chunks); 18192 used
TopTransactionContext: 8192 total in 1 blocks; 8136 free (0 chunks); 56 used
DeferredTriggerXact: 2088960 total in 8 blocks; 97384 free (6 chunks); 1991576 used
MessageContext: 57344 total in 3 blocks; 7552 free (2 chunks); 49792 used
PortalMemory: 8192 total in 1 blocks; 8040 free (0 chunks); 152 used
PortalHeapMemory: 1024 total in 1 blocks; 936 free (0 chunks); 88 used
ExecutorState: 4556232 total in 46 blocks; 3183264 free (8303 chunks); 1372968 used
ExprContext: 0 total in 0 blocks; 0 free (0 chunks); 0 used
ExecutorState: 528474112 total in 72 blocks; 760 free (1 chunks); 528473352 used
ExprContext: 0 total in 0 blocks; 0 free (0 chunks); 0 used
ExprContext: 0 total in 0 blocks; 0 free (0 chunks); 0 used
ExprContext: 0 total in 0 blocks; 0 free (0 chunks); 0 used
ExprContext: 0 total in 0 blocks; 0 free (0 chunks); 0 used
ExprContext: 8192 total in 1 blocks; 8176 free (0 chunks); 16 used
CacheMemoryContext: 516096 total in 6 blocks; 44208 free (2 chunks); 471888 used
raw_atitles_main_title_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
raw_atitles_attribs_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
raw_atitles_aka_title_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
movies_orig_title_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
movies_year_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
movies_title_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
movies_id_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_constraint_conrelid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_attrdef_adrelid_adnum_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
truc: 3144 total in 2 blocks; 1848 free (0 chunks); 1296 used
atitles_title_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
atitles_movie_id_idx: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_index_indrelid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_type_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_type_typname_nsp_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_statistic_relid_att_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_shadow_usesysid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_rewrite_rel_rulename_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_proc_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_proc_proname_args_nsp_index: 3144 total in 2 blocks; 1784 free (0 chunks); 1360 used
pg_operator_oprname_l_r_n_index: 3144 total in 2 blocks; 1784 free (0 chunks); 1360 used
pg_namespace_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_namespace_nspname_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_language_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_language_name_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_inherits_relid_seqno_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_group_sysid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_group_name_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_conversion_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_conversion_name_nsp_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_conversion_default_index: 3144 total in 2 blocks; 1784 free (0 chunks); 1360 used
pg_opclass_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_opclass_am_name_nsp_index: 3144 total in 2 blocks; 1848 free (0 chunks); 1296 used
pg_cast_source_target_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_attribute_relid_attnam_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_amop_opr_opc_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_aggregate_fnoid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_shadow_usename_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_trigger_tgrelid_tgname_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_operator_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_amproc_opc_procnum_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_amop_opc_strategy_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_index_indexrelid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_attribute_relid_attnum_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_class_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_amproc_opc_procnum_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_operator_oid_index: 1024 total in 1 blocks; 640 free (0 chunks); 384 used
pg_amop_opc_strategy_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
pg_class_relname_nsp_index: 1024 total in 1 blocks; 320 free (0 chunks); 704 used
MdSmgr: 8192 total in 1 blocks; 6120 free (0 chunks); 2072 used
DynaHash: 8192 total in 1 blocks; 7064 free (0 chunks); 1128 used
DynaHashTable: 8192 total in 1 blocks; 5080 free (0 chunks); 3112 used
DynaHashTable: 8192 total in 1 blocks; 2008 free (0 chunks); 6184 used
DynaHashTable: 8192 total in 1 blocks; 3520 free (0 chunks); 4672 used
DynaHashTable: 8192 total in 1 blocks; 3520 free (0 chunks); 4672 used
DynaHashTable: 24576 total in 2 blocks; 13240 free (4 chunks); 11336 used
DynaHashTable: 0 total in 0 blocks; 0 free (0 chunks); 0 used
DynaHashTable: 0 total in 0 blocks; 0 free (0 chunks); 0 used
DynaHashTable: 0 total in 0 blocks; 0 free (0 chunks); 0 used
DynaHashTable: 0 total in 0 blocks; 0 free (0 chunks); 0 used
DynaHashTable: 0 total in 0 blocks; 0 free (0 chunks); 0 used
ErrorContext: 8192 total in 1 blocks; 8176 free (8 chunks); 16 used
==============================================================================

--
%!PS
297.6 420.9 translate 90 rotate 0 setgray gsave 0 1 1{pop 0 180 moveto 100
180 170 100 170 -10 curveto 180 -9 180 -9 190 -10 curveto 190 100 100 180
0 180 curveto fill 180 rotate}for grestore/Bookman-LightItalic findfont
240 scalefont setfont -151.536392 -63.7998886 moveto (bp)show showpage