On Sun, Jul 28, 2024 at 8:34 AM Laurenz Albe <laurenz.albe@xxxxxxxxxxx> wrote:
On Sat, 2024-07-27 at 15:48 -0400, Ron Johnson wrote:
> > If your machine is too weak to handle the combined workload of restore +
> > autovacuum, that might get you something. Otherwise, you are just cheating:
> > the restore might be faster, but the database is not usable before autovacuum
> > and autoanalyze have proessed all restored tables.
>
> I 100% disagree with this: autovacuum is not necessary during pg_restore
> (presuming there's only one database in the instance).
It is not necessary during restore, but it is necessary if you want to use
the database after the restore. Well, you can manually VACUUM and ANALYZE the
database, but why not do it automatically?
I think that there are very few good reasons to ever disable autovacuum, and
a restore is not among them.
My experience is that autovacuum=off pg_restore -Fd -j$BigNum + vacuumdb -Zj$BigNum is faster than letting autoanalyze=on pg_restore -Fd -j$BigNum.
> Heck, it might not even be vital if you carefully monitor the other databases
> in the instance.
?
Tables in a freshly vacuum database won't need vacuuming again "for a while" unless they're really, really busy. Analyzing is a different story, but targeted manual analyzes work just as well.
