| From: | Andrey Borodin <x4mmm(at)yandex-team(dot)ru> |
|---|---|
| To: | Christoph Berg <myon(at)debian(dot)org> |
| Cc: | Tomas Vondra <tomas(at)vondra(dot)me>, wenhui qiu <qiuwenhuifx(at)gmail(dot)com>, Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at>, Andres Freund <andres(at)anarazel(dot)de>, Jelte Fennema-Nio <postgres(at)jeltef(dot)nl>, Michael Paquier <michael(at)paquier(dot)xyz>, Japin Li <japinli(at)hotmail(dot)com>, Fujii Masao <masao(dot)fujii(at)gmail(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>, John Naylor <johncnaylorls(at)gmail(dot)com> |
| Subject: | Re: WAL compression setting after PostgreSQL LZ4 default change |
| Date: | 2026-07-31 14:58:32 |
| Message-ID: | 856ABCB3-1D3A-4E1D-B694-C258E95CA1AC@yandex-team.ru |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
> On 31 Jul 2026, at 18:10, Christoph Berg <myon(at)debian(dot)org> wrote:
>
> zstd for WAL
FWIW on 19beta2, one client: a seqscan setting hint bits on a freshly
checkpointed 380MB table with wal_log_hints on, so ~47k full-page images
and little else. Best of three: off 765ms, pglz 1402ms, lz4 444ms, zstd
797ms, writing 382/105/107/67 MB of WAL (fsync off, so the I/O saving is
understated). lz4 is the only setting faster than no compression at all,
while pglz costs nearly double for the size lz4 gives away for free. zstd
compresses a third better but pays for it in CPU, partly by allocating a
ZSTD_CCtx per FPI - see the nearby thread "Compression of bigger WAL
records". +1 for "on" meaning lz4 where available.
Best regards, Andrey Borodin.
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Nathan Bossart | 2026-07-31 15:01:33 | Re: bump minimum supported version of psql and pg_{dump,dumpall,upgrade} to v10 |
| Previous Message | Vladlen Popolitov | 2026-07-31 14:55:04 | Re: zic: fix PostgreSQL build failure on filesystems without hard link support |