On Tue, Apr 3, 2018 at 11:29 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Also, scribbling on tables as sensitive as pg_class is just asking for
> trouble IMO. I don't see anything in this test, for example, that
> prevents autovacuum from running and causing a PANIC before the test
> can complete.
+1
> Even with AV off, there's a good chance that clobber-
> cache-always animals will fall over because they do so many more
> physical accesses to the system catalogs. I'd suggest inducing the
> corruption in some user table(s) that we can more tightly constrain
> the source server's accesses to.
I've simulated quite a few novel corruption scenarios using pg_hexedit
in the past year. It would be nice if pg_prewarm offered an easy way
to evict from shared_buffers for repeated testing. Obviously you can
accomplish the same thing in other ways, but that isn't ideal, and
particularly hinders automated testing.
--
Peter Geoghegan