Re: Vacuum, Freeze and Analyze: the big picture

On 2013-06-12 14:43:53 -0700, Jeff Janes wrote:
> > The default suggestion that frequently seems to be made is just to
> > disable autovac cost limitations because of that.

> Is there general agreement that this suggestion is bad?  Setting
> autovacuum_vacuum_cost_delay to zero is basically saying "I dare you to do
> your best to destroy my IO performance."  So it is not surprising that this
> just moves one from the frying pan to the fire, or maybe the reverse.

It sure as heck is better than an anti wraparound shutdown every week
because autovacuum doesn't finish all relations in time. More often than
not a large part of the relations has already been frozen so it won't
dirty all that much.
I think it's actually a quite sensible setting in many situations given
the state of the current controls.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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