Re: CHECKPOINT unlogged data

Christoph Berg <myon@debian.org>

From: Christoph Berg <myon@debian.org>

To: Andres Freund <andres@anarazel.de>

Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>

Date: 2025-05-30T16:55:28Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Add FLUSH_UNLOGGED option to CHECKPOINT command.
- 8d33fbacbac9 19 (unreleased) landed
Add MODE option to CHECKPOINT command.
- 2f698d7f4b7b 19 (unreleased) landed
Add option list to CHECKPOINT command.
- a4f126516e68 19 (unreleased) landed
Rename CHECKPOINT_FLUSH_ALL to CHECKPOINT_FLUSH_UNLOGGED.
- cd8324cc89a9 19 (unreleased) landed
Rename CHECKPOINT_IMMEDIATE to CHECKPOINT_FAST.
- bb938e2c3c7a 19 (unreleased) landed

Re: Andres Freund
> Hi,
> 
> On 2025-05-30 18:17:45 +0200, Christoph Berg wrote:
> > A customer reported to use CHECKPOINT before shutdowns to make the
> > shutdowns themselves faster and asked if it was possible to make
> > CHECKPOINT optionally also write out unlogged table data for that
> > purpose. I think the idea makes sense, so there's the patch.
> 
> I've seen the need for this quite a few times, fwiw. So +1 to the idea.

Do we want to officially mention this use case in checkpoint.sgml? I've
already replaced the "is not intended for use during normal operation"
wording by "not required during normal operation", but we might go one
step further and endorse it.

Christoph