Re: xid wraparound danger due to INDEX_CLEANUP false

On Wed, 6 May 2020 at 07:14, Peter Geoghegan <pg@bowt.ie> wrote:
>
> On Tue, May 5, 2020 at 2:52 PM Masahiko Sawada
> <masahiko.sawada@2ndquadrant.com> wrote:
> > So IIUC the problem is that since we skip both,
> > oldst_btpo_xact could be seen as a "future" xid during vacuum. Which
> > will be a cause of that vacuum misses pages which can actually be
> > recycled.
>
> This is also my understanding of the problem.
>
> > I think we can fix this issue by calling vacuumcleanup callback when
> > an anti-wraparound vacuum even if INDEX_CLEANUP is false. That way we can
> > let index AM make decisions whether doing cleanup index at least once
> > until XID wraparound, same as before.
>
> +1
>
> Can you work on a patch?

Yes, I'll submit a bug fix patch.

Regards,

-- 
Masahiko Sawada            http://www.2ndQuadrant.com/
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