On Wed, 2022-10-19 at 14:58 -0700, Peter Geoghegan wrote:
> Why should the PROC_VACUUM_FOR_WRAPAROUND behavior happen on
> *exactly*
> the same timeline as the one used to launch an antiwraparound
> autovacuum, though?
The terminology is getting slightly confusing here: by
"antiwraparound", you mean that it's not skipping unfrozen pages, and
therefore is able to advance relfrozenxid. Whereas the
PROC_VACUUM_FOR_WRAPAROUND is the same thing, except done with greater
urgency because wraparound is imminent. Right?
> There is no inherent reason why we have to do both
> things at exactly the same XID-age-wise time. But there is reason to
> think that doing so could make matters worse rather than better [1].
Can you explain?
Regards,
Jeff Davis