Re: autovacuum maintenance_work_mem

Excerpts from Josh Berkus's message of mar nov 16 15:52:14 -0300 2010:
> 
> > I think the difficulty is figuring out what to get the existing
> > workers to give us some memory when a new one comes along.  You want
> > the first worker to potentially use ALL the memory... until worker #2
> > arrives.
> 
> Yeah, doing this would mean that you couldn't give worker #1 all the
> memory, because on most OSes it can't release the memory even if it
> wants to.

Hmm, good point.

> Relevant to this is the question: *when* does vacuum do its memory
> allocation?  Is memory allocation reasonably front-loaded, or does
> vacuum keep grabbing more RAM until it's done?

All at start.

-- 
Álvaro Herrera <alvherre@commandprompt.com>
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