On Thu, 2026-07-16 at 11:08 -0400, Andres Freund wrote:
> On 2026-07-16 17:00:58 +0200, Tomas Vondra wrote:
> > * the proposal is to change what 'on' means - currently it's always
> > pglz, but the proposal would change this to the "best" available
> > algorithm (so lz4)
> >
> > * the wal_compression default would remain "off"
> >
> > I think this proposal makes sense, and at least Michael and Christoph
> > seem to agree with that.
>
> +1 from me too.
>
> I've seen way too many incidents where wal_compression was very useful but due
> to the use of pglz slowed down crucial, single threaded, parts of the workload
> down so much that it had to be disabled again. We should not make it our
> users responsibility to know that the 'on' maps to an almost unusably slow
> compression algorithm.
+1
It would be compelling to make this change for v19, so that it is in line
with the change for "default_toast_compression". But I guess it is too late
in the cycle for that.
Yours,
Laurenz Albe
