Re: Auto-tuning work_mem and maintenance_work_mem

On Wed, Oct 16, 2013 at 04:25:37PM -0400, Andrew Dunstan wrote:
> 
> On 10/09/2013 11:06 AM, Andrew Dunstan wrote:
> >
> >
> >
> >The assumption that each connection won't use lots of work_mem is
> >also false, I think, especially in these days of connection
> >poolers.
> >
> >
> 
> 
> Andres has just been politely pointing out to me that my knowledge
> of memory allocators is a little out of date (i.e. by a decade or
> two), and that this memory is not in fact likely to be held for a
> long time, at least on most modern systems. That undermines
> completely my reasoning above.
> 
> Given that, it probably makes sense for us to be rather more liberal
> in setting work_mem that I was suggesting.

Ah, yes, this came up last year (MMAP_THRESHOLD):
http://www.postgresql.org/message-id/20120730161416.GB10877@momjian.us

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http://enterprisedb.com
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