Re: BUG #17257: (auto)vacuum hangs within lazy_scan_prune()

On Sat, Jan 6, 2024 at 3:24 PM Noah Misch <noah@leadboat.com> wrote:
> On Sun, Dec 31, 2023 at 03:53:34PM -0800, Peter Geoghegan wrote:
> > I am aware of a production database that appears to run into the same
> > problem. Inserts and concurrent cross-partition updates are used
> > heavily on this instance (the table in question uses partitioning).
> > Perhaps you happened upon a similar problematic production database,
> > and found this thread when researching the issue? Maybe we've both
> > seen the same problem in the wild?
>
> I did find this thread while researching the symptoms I was seeing.  No
> partitioning where I saw them.

I'm starting to think that partitioning was just a red herring. The
instance had problems in the presence of DELETEs, not UPDATEs (or
cross-partition UPDATEs).

Did the affected system that you investigated happen to have an
atypically high number of databases? The system 15.4 system that I saw
the problem on had almost 3,000 databases.

--
Peter Geoghegan