Horton

Re: USE_BARRIER_SMGRRELEASE on Linux?

Nathan Bossart <nathandbossart@gmail.com>

View thread View on postgr.es
From: Nathan Bossart <nathandbossart@gmail.com>
To: Andres Freund <andres@anarazel.de>
Cc: Thomas Munro <thomas.munro@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2022-02-16T06:57:32Z
Lists: pgsql-hackers

Attachments

On Tue, Feb 15, 2022 at 10:14:04PM -0800, Nathan Bossart wrote:
> It looks like register_unlink_segment() is called prior to the checkpoint,
> but the checkpointer is not calling RememberSyncRequest() until after
> SyncPreCheckpoint().  This means that the requests are registered with the
> next checkpoint cycle count, so they aren't processed until the next
> checkpoint.

Calling AbsorbSyncRequests() before advancing the checkpoint cycle counter
seems to fix the issue.  However, this requires moving SyncPreCheckpoint()
out of the critical section in CreateCheckPoint().  Patch attached.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com

Commits

  1. Fix race between DROP TABLESPACE and checkpointing.