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| author | Jeff Davis <jdavis@postgresql.org> | 2015-02-21 17:24:48 -0800 |
|---|---|---|
| committer | Jeff Davis <jdavis@postgresql.org> | 2015-02-21 17:24:48 -0800 |
| commit | b419865a814abbca12bdd6eef6a3d5ed67f432e1 (patch) | |
| tree | e1cce5a0394a5d83f8f42e1b33e265bd12b69613 /src/backend/utils/adt/array_userfuncs.c | |
| parent | e9fd5545de3bb4efe163af4a9c957badac86ccd7 (diff) | |
| download | postgresql-b419865a814abbca12bdd6eef6a3d5ed67f432e1.tar.gz postgresql-b419865a814abbca12bdd6eef6a3d5ed67f432e1.zip | |
In array_agg(), don't create a new context for every group.
Previously, each new array created a new memory context that started
out at 8kB. This is incredibly wasteful when there are lots of small
groups of just a few elements each.
Change initArrayResult() and friends to accept a "subcontext" argument
to indicate whether the caller wants the ArrayBuildState allocated in
a new subcontext or not. If not, it can no longer be released
separately from the rest of the memory context.
Fixes bug report by Frank van Vugt on 2013-10-19.
Tomas Vondra. Reviewed by Ali Akbar, Tom Lane, and me.
Diffstat (limited to 'src/backend/utils/adt/array_userfuncs.c')
| -rw-r--r-- | src/backend/utils/adt/array_userfuncs.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/backend/utils/adt/array_userfuncs.c b/src/backend/utils/adt/array_userfuncs.c index 7f7c2569861..5781b952f97 100644 --- a/src/backend/utils/adt/array_userfuncs.c +++ b/src/backend/utils/adt/array_userfuncs.c @@ -520,8 +520,13 @@ array_agg_transfn(PG_FUNCTION_ARGS) elog(ERROR, "array_agg_transfn called in non-aggregate context"); } - state = PG_ARGISNULL(0) ? NULL : (ArrayBuildState *) PG_GETARG_POINTER(0); + if (PG_ARGISNULL(0)) + state = initArrayResult(arg1_typeid, aggcontext, false); + else + state = (ArrayBuildState *) PG_GETARG_POINTER(0); + elem = PG_ARGISNULL(1) ? (Datum) 0 : PG_GETARG_DATUM(1); + state = accumArrayResult(state, elem, PG_ARGISNULL(1), @@ -595,7 +600,12 @@ array_agg_array_transfn(PG_FUNCTION_ARGS) elog(ERROR, "array_agg_array_transfn called in non-aggregate context"); } - state = PG_ARGISNULL(0) ? NULL : (ArrayBuildStateArr *) PG_GETARG_POINTER(0); + + if (PG_ARGISNULL(0)) + state = initArrayResultArr(arg1_typeid, InvalidOid, aggcontext, false); + else + state = (ArrayBuildStateArr *) PG_GETARG_POINTER(0); + state = accumArrayResultArr(state, PG_GETARG_DATUM(1), PG_ARGISNULL(1), |