Re: Proposal: Log inability to lock pages during vacuum

Greg Stark wrote:

> I agree bloat isn't really a threat, but what about the relfrozenxid?
> If we skip even one page we don't get to advance it and retrying could
> eliminate those skipped pages and allow us to avoid a vacuum freeze
> which can be really painful. Of course that only works if you can be
> sure you haven't overflowed and forgotten any skipped pages and if you
> don't find the page still pinned every time until you eventually give
> up on it.

We never advance relfrozenxid nowadays unless it's a whole-table scan;
and once we commit to doing those (vacuum_freeze_table_age is past), we
don't skip pages anymore.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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