Fix memory leak in pgoutput with streamed prepared transactions. pgoutput records the toplevel XID in the relation's streamed_txns list, allocated in CacheMemoryContext, when it sends a relation's schema during a streamed transaction. We clean up that list at stream commit and stream abort, but missed stream prepare, so the XIDs stay around until a relcache invalidation for the relation or until the walsender exits.
Fix by cleaning up the cache after writing the stream prepare message, marking the schema as sent as we do at stream commit. The subscriber applies the spooled relation messages at PREPARE time and its relation map isn't rolled back by ROLLBACK PREPARED, so we don't need to send the schema again even if the prepared transaction eventually aborts. Oversight in commit 63cf61cdeb7b. Author: Ayush Tiwari <[email protected]> Reviewed-by: Hayato Kuroda <[email protected]> Reviewed-by: Masahiko Sawada <[email protected]> Discussion: https://postgr.es/m/CAJTYsWWt5aaKHCnV=jnowabzspd-wbnhwlnddqtesdqrq-b...@mail.gmail.com Backpatch-through: 15 Branch ------ REL_18_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/a477847ebe2a1f700ce1844a8b718fdd66e9b7d0 Modified Files -------------- src/backend/replication/pgoutput/pgoutput.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-)
