diff options
| author | Andres Freund | 2017-10-08 22:08:25 +0000 |
|---|---|---|
| committer | Andres Freund | 2017-10-08 22:08:25 +0000 |
| commit | 84ad4b036d975ad1be0f52251bac3a06463c9811 (patch) | |
| tree | 452e84ebb7d11ba87b6ad257fec34d1782aa0a34 /src/include | |
| parent | 643c27e36ff38f40d256c2a05b51a14ae2b26077 (diff) | |
Reduce memory usage of targetlist SRFs.
Previously nodeProjectSet only released memory once per input tuple,
rather than once per returned tuple. If the computation of an
individual returned tuple requires a lot of memory, that can lead to
problems.
Instead change things so that the expression context can be reset once
per output tuple, which requires a new memory context to store SRF
arguments in.
This is a longstanding issue, but was hard to fix before 9.6, due to
the way tSRFs where evaluated. But it's fairly easy to fix now. We
could backpatch this into 10, but given there've been fewc omplaints
that doesn't seem worth the risk so far.
Reported-By: Lucas Fairchild
Author: Andres Freund, per discussion with Tom Lane
Discussion: https://postgr.es/m/4514.1507318623@sss.pgh.pa.us
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/executor/executor.h | 1 | ||||
| -rw-r--r-- | src/include/nodes/execnodes.h | 1 |
2 files changed, 2 insertions, 0 deletions
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index 770881849c..37fd6b2700 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -400,6 +400,7 @@ extern SetExprState *ExecInitFunctionResultSet(Expr *expr, ExprContext *econtext, PlanState *parent); extern Datum ExecMakeFunctionResultSet(SetExprState *fcache, ExprContext *econtext, + MemoryContext argContext, bool *isNull, ExprDoneCond *isDone); diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index c6d3021c85..c46113444f 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -946,6 +946,7 @@ typedef struct ProjectSetState ExprDoneCond *elemdone; /* array of per-SRF is-done states */ int nelems; /* length of elemdone[] array */ bool pending_srf_tuples; /* still evaluating srfs in tlist? */ + MemoryContext argcontext; /* context for SRF arguments */ } ProjectSetState; /* ---------------- |