Re: Testing autovacuum wraparound (including failsafe) - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: Testing autovacuum wraparound (including failsafe)
Date
Msg-id CAH2-WznqVesSxWOejO0WCemEBo5d_g4c11pU=LbO2+o-BMAcYw@mail.gmail.com
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In response to Re: Testing autovacuum wraparound (including failsafe)  (Masahiko Sawada <sawada.mshk@gmail.com>)
List pgsql-hackers
On Tue, May 18, 2021 at 12:10 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> Since there is the condition "vacrel->num_index_scans == 0" we could
> enter the failsafe mode even if the table is less than 4GB, if we
> enter lazy_check_wraparound_failsafe() after executing more than one
> index scan. Whereas a vacuum on the table that is less than 4GB and
> has no index never enters the failsafe mode. I think we can remove
> this condition since I don't see the reason why we don't allow to
> enter the failsafe mode only when the first-time index scan in the
> case of such tables. What do you think?

I'm convinced -- this does seem like premature optimization now.

I pushed a version of the patch that removes that code just now.

Thanks
-- 
Peter Geoghegan



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