From 85a0781334a204c15c9c6ea9d3e6c75334c2beb6 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 14 Apr 2017 17:51:25 -0400 Subject: [PATCH] Use one transaction while reading postgres.bki, not one per line. AFAICT, the only actual benefit of closing a bootstrap transaction is to reclaim transient memory. We can do that a lot more cheaply by just doing a MemoryContextReset on a suitable context. This gets the runtime of the "bootstrap" phase of initdb down to the point where, at least by eyeball, it's quite negligible compared to the rest of the phases. Per discussion with Andres Freund. Discussion: https://postgr.es/m/9244.1492106743@sss.pgh.pa.us --- src/backend/bootstrap/bootparse.y | 18 +++++++++++++----- src/backend/bootstrap/bootstrap.c | 3 +++ 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/src/backend/bootstrap/bootparse.y b/src/backend/bootstrap/bootparse.y index 867f77076d..de3695c7e0 100644 --- a/src/backend/bootstrap/bootparse.y +++ b/src/backend/bootstrap/bootparse.y @@ -22,7 +22,6 @@ #include "access/htup.h" #include "access/itup.h" #include "access/tupdesc.h" -#include "access/xact.h" #include "bootstrap/bootstrap.h" #include "catalog/catalog.h" #include "catalog/heap.h" @@ -49,6 +48,7 @@ #include "storage/off.h" #include "storage/smgr.h" #include "tcop/dest.h" +#include "utils/memutils.h" #include "utils/rel.h" @@ -63,19 +63,27 @@ #define YYMALLOC palloc #define YYFREE pfree +static MemoryContext per_line_ctx = NULL; + static void do_start(void) { - StartTransactionCommand(); - elog(DEBUG4, "start transaction"); + Assert(CurrentMemoryContext == CurTransactionContext); + /* First time through, create the per-line working context */ + if (per_line_ctx == NULL) + per_line_ctx = AllocSetContextCreate(CurTransactionContext, + "bootstrap per-line processing", + ALLOCSET_DEFAULT_SIZES); + MemoryContextSwitchTo(per_line_ctx); } static void do_end(void) { - CommitTransactionCommand(); - elog(DEBUG4, "commit transaction"); + /* Reclaim memory allocated while processing this line */ + MemoryContextSwitchTo(CurTransactionContext); + MemoryContextReset(per_line_ctx); CHECK_FOR_INTERRUPTS(); /* allow SIGINT to kill bootstrap run */ if (isatty(0)) { diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c index 46c207c86c..4c28b2b821 100644 --- a/src/backend/bootstrap/bootstrap.c +++ b/src/backend/bootstrap/bootstrap.c @@ -18,6 +18,7 @@ #include #include "access/htup_details.h" +#include "access/xact.h" #include "bootstrap/bootstrap.h" #include "catalog/index.h" #include "catalog/pg_collation.h" @@ -496,7 +497,9 @@ BootstrapModeMain(void) /* * Process bootstrap input. */ + StartTransactionCommand(); boot_yyparse(); + CommitTransactionCommand(); /* * We should now know about all mapped relations, so it's okay to write -- 2.40.0