From 9126f6f737828295947f9b3d82dc5174f2ff64b4 Mon Sep 17 00:00:00 2001 From: Andres Freund Date: Tue, 13 Nov 2018 12:18:25 -0800 Subject: [PATCH v14 7/7] Rationalize expression context reset in ExecModifyTable(). The current pattern of reseting expressions both in ExecProcessReturning() and ExecOnConflictUpdate() makes it harder than necessary to reason about memory lifetimes. It also requires materializing slots unnecessarily, although this patch doesn't take advantage of the fact that that's not necessary anymore. Instead reset the expression context once for each input tuple. Author: Ashutosh Bapat Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de --- src/backend/executor/nodeModifyTable.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index d29162bab79..71074ebe120 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -163,12 +163,6 @@ ExecProcessReturning(ResultRelInfo *resultRelInfo, ProjectionInfo *projectReturning = resultRelInfo->ri_projectReturning; ExprContext *econtext = projectReturning->pi_exprContext; - /* - * Reset per-tuple memory context to free any expression evaluation - * storage allocated in the previous cycle. - */ - ResetExprContext(econtext); - /* Make tuple and any needed join variables available to ExecProject */ if (tupleSlot) econtext->ecxt_scantuple = tupleSlot; @@ -1453,13 +1447,7 @@ ExecOnConflictUpdate(ModifyTableState *mtstate, elog(ERROR, "unrecognized heap_lock_tuple status: %u", test); } - /* - * Success, the tuple is locked. - * - * Reset per-tuple memory context to free any expression evaluation - * storage allocated in the previous cycle. - */ - ResetExprContext(econtext); + /* Success, the tuple is locked. */ /* * Verify that the tuple is visible to our MVCC snapshot if the current @@ -2028,6 +2016,14 @@ ExecModifyTable(PlanState *pstate) */ ResetPerTupleExprContext(estate); + /* + * Reset per-tuple memory context used for processing on conflict and + * returning clauses, to free any expression evaluation storage + * allocated in the previous cycle. + */ + if (pstate->ps_ExprContext) + ResetExprContext(pstate->ps_ExprContext); + planSlot = ExecProcNode(subplanstate); if (TupIsNull(planSlot)) -- 2.18.0.rc2.dirty