On 11/8/22 18:06, Wells Oliver wrote:
> Upgraded 13.7 to 14.4 on RDS by restoring from a snapshot and upgrading that.
Off-topic, but did you rebuild all indices with text columns? That might
not be relevant in RDS (who knows exactly what's underneath the hood?) but
it might be.
> My configuration files and instance type are exactly the same. After
> upgrading, I ran vacuumdb -Z -j 8 and that did its thing.
> The upgraded database is slower. I'm running EXPLAIN ANALYZE for various
> queries and it's getting to the same plan, but it's taking longer to execute.
>
> I've always felt after major upgrades there's some element to "priming the
> database" where it seems to be much faster a few days in after broader
> usage. I realize it sounds absurd but I'll swear by this being my
> experience. So I'm willing to think to some degree that queries will
> execute faster the more people use the upgraded database.
>
> Just wondering if there is anything I might specifically look at that
> would account for some of the slowness.
https://dba.stackexchange.com/a/295145/63913
That answer is about loading the cache yourself, either the old school
SELECT * FROM foo WHERE ... method, or using using the pg_prewarm extension.
--
Angular momentum makes the world go 'round.
