Re: max_slot_wal_keep_size and wal_keep_segments

On Wed, Jul 1, 2020 at 04:25:35PM -0400, Alvaro Herrera wrote:
> On 2020-Jul-01, Bruce Momjian wrote:
>
> > We have the following wal*size GUC settings:
> >
> > SELECT name FROM pg_settings WHERE name LIKE '%wal%size%';
> > name
> > ------------------------
> > max_slot_wal_keep_size
> > max_wal_size
> > min_wal_size
> > wal_block_size
> > wal_segment_size
> >
> > Does wal_keep_size make sense here?
>
> I think it does. What do you think?
>
> Are you suggesting that "keep_wal_size" is better, since it's more in
> line with min/max? I lean towards no.

No, I am more just asking since I saw wal_keep_size as a special version
of wal_size. I don't have a firm opinion.

>
> (I think it's okay to conceptually separate these three options from
> wal_block_size, since that's a compile time option and thus it's an
> introspective GUC rather than actual configuration, but as I recall that
> argument does not hold for wal_segment_size. But at one point, even that
> one was an introspective GUC too.)

Yep, just asking.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EnterpriseDB https://enterprisedb.com

The usefulness of a cup is in its emptiness, Bruce Lee