Hi, On 2022-04-14 12:01:23 -0400, Tom Lane wrote: > Noah Misch <n...@leadboat.com> writes: > > On Wed, Apr 13, 2022 at 06:51:12PM -0700, Andres Freund wrote: > >> Noah, any chance you could enable log_autovacuum_min_duration=0 on > >> wrasse? > > > Done. Also forced hourly builds.
Thanks! Can you repro the problem manually on wrasse, perhaps even outside the buildfarm script? That might be simpler than debugging via the BF... > Thanks! We now have two failing runs with the additional info [1][2], > and in both, it's clear that the first autovac worker doesn't launch > until 1 minute after postmaster start, by which time we're long done > with the test scripts of interest. So whatever is breaking this is > not an autovac worker. I did some experiments around that too, and didn't find any related problems. For a second I was wondering if it's caused by the time of initdb (which ends up with a working pgstat snapshot now, but didn't before), but that's just a few more seconds. While the BF scripts don't show timestamps for initdb, the previous step's log output confirms that it's just a few seconds... > I think I'm going to temporarily add a couple of queries to check > what tenk1's relallvisible actually is, just so we can confirm > positively that that's what's causing the plan change. (I'm also > curious about whether the CREATE INDEX steps manage to change it > at all.) I wonder if we should make VACUUM log the VERBOSE output at DEBUG1 unconditionally. This is like the third bug where we needed that information, and it's practically impossible to include in regression output. Then we'd know what the xid horizon is, whether pages were skipped, etc. It also just generally seems like a good thing. Greetings, Andres Freund
