Re: Really really slow select count(*)

felix wrote:
> and do you agree that I should turn CLUSTER ON ?
> I have no problem to stop all tasks to this table at night and just
> reload it

You don't turn it on; it's a one time operation that does a cleanup.  It
is by far the easiest way to clean up the mess you have right now.
Moving forward, if you have max_fsm_pages set to an appropriate number,
you shouldn't end up back in this position again.  But VACUUM along
won't get you out of there, and VACUUM FULL is always a worse way to
clean this up than CLUSTER.

--
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
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