Re: [PING] fallocate() causes btrfs to never compress postgresql files

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>

To: Thomas Munro <thomas.munro@gmail.com>

Cc: Dimitrios Apostolou <jimis@gmx.net>, Tomas Vondra <tomas@vondra.me>, pgsql-hackers@lists.postgresql.org, Andres Freund <andres@anarazel.de>, Melanie Plageman <melanieplageman@gmail.com>, Heikki Linnakangas <hlinnaka@iki.fi>, Kyotaro Horiguchi <horikyota.ntt@gmail.com>, David Rowley <dgrowleyml@gmail.com>, John Naylor <john.naylor@enterprisedb.com>

Date: 2025-05-31T15:42:01Z

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 file_extend_method=posix_fallocate,write_zeros.
- e37b59802846 16.12 landed
- 4dac22aa10d2 17.8 landed
- f94e9141a0bb 19 (unreleased) landed
- 33e3de6d77e8 18.2 landed
Add smgrzeroextend(), FileZero(), FileFallocate()
- 4d330a61bb19 16.0 cited

Thomas Munro <thomas.munro@gmail.com> writes:
> It's slightly tricky to get smgr to behave differently because of the
> contents of a system catalogue!

The mere thought makes me blanch.  I'm okay with the GUC part,
but I do not think we should put in 0002 --- the odds of
causing serious problems greatly outweigh the value, IMO.
Fundamental layering violations tend to bite you on tender
parts of your anatomy.

			regards, tom lane