Re: New strategies for freezing, advancing relfrozenxid early

Hi!

I'll try to apply this patch onto my branch with Pluggable TOAST to test
these mechanics with new TOAST. Would reply on the result. It could
be difficult though, because both have a lot of changes that affect
the same code.

>I'm not sure how much this would help with bloat. I suspect that it
>could make a big difference with the right workload. If you always
>need frequent autovacuums, just to deal with bloat, then there is
>never a good time to run an aggressive antiwraparound autovacuum. An
>aggressive AV will probably end up taking much longer than the typical
>autovacuum that deals with bloat. While the aggressive AV will remove
>as much bloat as any other AV, in theory, that might not help much. If
>the aggressive AV takes as long as (say) 5 regular autovacuums would
>have taken, and if you really needed those 5 separate autovacuums to
>run, just to deal with the bloat, then that's a real problem. The
>aggressive AV effectively causes bloat with such a workload.

On Tue, Dec 20, 2022 at 12:01 PM Jeff Davis <pgsql(at)j-davis(dot)com> wrote:

> On Sun, 2022-12-18 at 14:20 -0800, Peter Geoghegan wrote:
> > Attached is v10, which fixes this issue, but using a different
> > approach to the one I sketched here.
>
> In 0001, it's fairly straightforward rearrangement and looks like an
> improvement to me. I have a few complaints, but they are about pre-
> existing code that you moved around, and I like that you didn't
> editorialize too much while just moving code around. +1 from me.
>
>
> --
> Jeff Davis
> PostgreSQL Contributor Team - AWS
>
>
>
>
>

--
Regards,

--
Nikita Malakhov
Postgres Professional
https://postgrespro.ru/