On Thu, Apr 14, 2022 at 7:20 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > Oh! You mean that maybe the OldestXmin horizon was fine, but something > decided not to update hint bits (and therefore also not the all-visible > bit) anyway? Worth investigating I guess.
Yes. That is starting to seem like a plausible alternative explanation. > > I'd really like to know what the removable cutoff > > looks like for these VACUUM operations, which is something like > > Andres' VACUUM VERBOSE debug patch should tell us. > > Yeah. I'd hoped to investigate this manually and not have to clutter > the main repo with debugging commits. Suppose that the bug was actually in 06f5295af6, "Add single-item cache when looking at topmost XID of a subtrans XID". Doesn't that fit your timeline just as well? I haven't really started to investigate that theory (just putting dinner on here). Just a wild guess at this point. -- Peter Geoghegan
