From b635ac03e80237838bec8b224eb4dea97985fda3 Mon Sep 17 00:00:00 2001 From: David Rowley Date: Thu, 27 Jul 2023 14:47:05 +1200 Subject: [PATCH] Fix performance problem with new COPY DEFAULT code 9f8377f7a added code to allow COPY FROM insert a column's default value when the input matches the DEFAULT string specified in the COPY command. Here we fix some inefficient code which needlessly palloc0'd an array to store if we should use the default value or input value for the given column. This array was being palloc0'd and pfree'd once per row. It's much more efficient to allocate this once and just reset the values once per row. Reported-by: Masahiko Sawada Author: Masahiko Sawada Discussion: https://postgr.es/m/CAD21AoDvDmUQeJtZrau1ovnT_smN940%3DKp6mszNGK3bq9yRN6g%40mail.gmail.com Backpatch-through: 16, where 9f8377f7a was introduced. --- src/backend/commands/copyfrom.c | 1 + src/backend/commands/copyfromparse.c | 4 +--- 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index 80bca79cd0..b47cb5c66d 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1609,6 +1609,7 @@ BeginCopyFrom(ParseState *pstate, } } + cstate->defaults = (bool *) palloc0(tupDesc->natts * sizeof(bool)); /* initialize progress */ pgstat_progress_start_command(PROGRESS_COMMAND_COPY, diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c index d2e8c74402..232768a6e1 100644 --- a/src/backend/commands/copyfromparse.c +++ b/src/backend/commands/copyfromparse.c @@ -871,7 +871,7 @@ NextCopyFrom(CopyFromState cstate, ExprContext *econtext, /* Initialize all values for row to NULL */ MemSet(values, 0, num_phys_attrs * sizeof(Datum)); MemSet(nulls, true, num_phys_attrs * sizeof(bool)); - cstate->defaults = (bool *) palloc0(num_phys_attrs * sizeof(bool)); + MemSet(cstate->defaults, false, num_phys_attrs * sizeof(bool)); if (!cstate->opts.binary) { @@ -1040,8 +1040,6 @@ NextCopyFrom(CopyFromState cstate, ExprContext *econtext, &nulls[defmap[i]]); } - pfree(cstate->defaults); - return true; }