Re: Turning off HOT/Cleanup sometimes

On Wed, Apr 22, 2015 at 06:07:00PM -0300, Alvaro Herrera wrote:
> > Good point, but doesn't vacuum remove the need for pruning as it removes
> > all the old rows?
> 
> Sure.  The point, I think, is to make autovacuum runs of some sort that
> don't actually vacuum but only do HOT-pruning.  Maybe this is a
> reasonable solution to the problem that queries don't prune anymore
> after Simon's patch.  If we made autovac HOT-prune periodically, we
> could have read-only queries prune only already-dirty pages.  Of course,
> that would need further adjustments to default number of autovac
> workers, I/O allocation, etc.

Do we really want to make vacuum more complex for this?  vacuum does
have the delay settings we would need though.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
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