Hello!
Thanks Guillaume and Ron!
I understand REINDEXING is not required, and as Guillaume highlighted, vacuum will still be needed after pg_restore.
Is it ok to perform a "standard" vacuum or do we need a "FULL" vacuum after pg_restore?
Also, I think finding tables which have dead rows and then performing vacuum on those tables only to save some time/processing here.
@Ron: Yes, we're using --jobs=`nproc` and it has significantly improved the pg_dump/pg_restore processes. I see there is a similar option "parallel' with VACUUM as well.
Thanks!
Hasan
On Sat, 7 May 2022 at 18:07, Guillaume Lelarge <guillaume@xxxxxxxxxxxx> wrote:
Le sam. 7 mai 2022 à 10:21, Ron <ronljohnsonjr@xxxxxxxxx> a écrit :On 5/6/22 21:35, Hasan Marzooq wrote:
Hello!
I've some questions around Backup & Restore.
1: Is it necessary to perform a VACUUM and REINDEXING operation after restoring the dump from Postgres 9.6 to Postgres 13? The dump size could be 1/2 TB to 1 TB.
Perform VACUUM after there have been many updates and deletes. There have been zero updates and deleted after pg_restore; therefore, no need to vacuum.
I disagree. You're right about the "zero updates and deletes", so no need to vacuum for bloat. But you need vacuum to get the visibility map of each relation, so that the planner can use index-only scans.
--Guillaume.
