Re: Auto-tuning work_mem and maintenance_work_mem

On 10/16/2013 01:25 PM, Andrew Dunstan wrote:
> 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 memory allocators is a little out of date (i.e. by a decade or two), and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.

Except that Opensolaris and FreeBSD still have the old memory allocation
behavior, as do older Linux kernels, many of which will remain in
production for years.  I have no idea what Windows' memory management
behavior is.

So this is a case of needing to know considerably more than the
available RAM to determine a good setting.

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com