Re: Memory leak of SMgrRelation object on standby

Jingtang Zhang <mrdrivingduck@gmail.com>

From: Jingtang Zhang <mrdrivingduck@gmail.com>

To: 邱宇航 <iamqyh@gmail.com>

Cc: Thomas Munro <thomas.munro@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, pgsql-hackers@lists.postgresql.org

Date: 2025-08-26T03:59:43Z

Lists: pgsql-hackers

Attachments

v4-0001-Fix-SMgrRelation-object-memory-leak-during-startup-r.patch (application/octet-stream) patch v4-0001

Hi~

> I purpose a patch which calls smgrdestroyall() when redo each
> XLOG_CHECKPOINT_ONLINE, so that it can keep the same frequency of calling
> smgrdestroyall() as background processes on primary. I don't call it for
> XLOG_CHECKPOINT_SHUTDOWN because the process is about to exit so that the
> memory will go soon, and don't call it for XLOG_CHECKPOINT_REDO because it
> seems to be a place holder only.


Oops. When redo XLOG_CHECKPOINT_SHUTDOWN, smgrdestroyall should also be
called, since the startup may not exit on standby.

The patch is updated.

—
Regards, Jingtang

Commits

Fix leak with SMgrRelations in startup process
- e2dd7b2acf27 17.7 landed
- 039301b3fceb 18.0 landed
- 8c8f7b199d90 19 (unreleased) landed
Give SMgrRelation pointers a well-defined lifetime.
- 21d9c3ee4ef7 17.0 cited