On Mon, 25 Apr 2022 at 12:45, Laurenz Albe <laurenz.a...@cybertec.at> wrote:
> > You could consider upgrade in several steps: > > - pg_upgrade to v14 on the current operating system > - use replication, than switchover to move to a current operating system > on a different > machine > - REINDEX CONCURRENTLY all indexes on string expressions > > You could get data corruption and bad query results between the second and > the third steps, > so keep that interval short. > We did something like this, with the addition of a step where we used a new-OS replica to run amcheck's bt_index_check() over all of the btree indexes to find those actually corrupted by the libc upgrade in practice with our data. It was a small fraction of them, and we were able to fit an offline reindex of those btrees and all texty non-btree indexes into an acceptable downtime window, with REINDEX CONCURRENTLY of everything else as a lower priority after the upgrade.
