From 0685c5c1b9225352bbaf4fe81c550f09508379ce Mon Sep 17 00:00:00 2001 From: Amit Kapila Date: Wed, 13 Jan 2021 08:31:45 +0530 Subject: [PATCH] Fix memory leak in SnapBuildSerialize. The memory for the snapshot was leaked while serializing it to disk during logical decoding. This memory will be freed only once walsender stops streaming the changes. This can lead to a huge memory increase when master logs Standby Snapshot too frequently say when the user is trying to create many replication slots. Reported-by: funnyxj.fxj@alibaba-inc.com Diagnosed-by: funnyxj.fxj@alibaba-inc.com Author: Amit Kapila Backpatch-through: 9.5 Discussion: https://postgr.es/m/033ab54c-6393-42ee-8ec9-2b399b5d8cde.funnyxj.fxj@alibaba-inc.com --- src/backend/replication/logical/snapbuild.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c index 3089f0d5dd..76c674ba8a 100644 --- a/src/backend/replication/logical/snapbuild.c +++ b/src/backend/replication/logical/snapbuild.c @@ -1480,7 +1480,7 @@ static void SnapBuildSerialize(SnapBuild *builder, XLogRecPtr lsn) { Size needed_length; - SnapBuildOnDisk *ondisk; + SnapBuildOnDisk *ondisk = NULL; char *ondisk_c; int fd; char tmppath[MAXPGPATH]; @@ -1679,6 +1679,9 @@ SnapBuildSerialize(SnapBuild *builder, XLogRecPtr lsn) out: ReorderBufferSetRestartPoint(builder->reorder, builder->last_serialized_snapshot); + /* be tidy */ + if (ondisk) + pfree(ondisk); } /*