Re: MusicBrainz postgres performance issues

On 2015-03-15 20:42:51 +0300, Ilya Kosmodemiansky wrote:
> On Sun, Mar 15, 2015 at 8:20 PM, Andres Freund <andres@2ndquadrant.com> wrote:
> > On 2015-03-15 11:09:34 -0600, Scott Marlowe wrote:
> >> shared_mem of 12G is almost always too large. I'd drop it down to ~1G or so.
> >
> > I think that's a outdated wisdom, i.e. not generally true.
>
> Quite agreed. With note, that proper configured controller with BBU is needed.

That imo doesn't really have anything to do with it. The primary benefit
of a BBU with writeback caching is accelerating (near-)synchronous
writes. Like the WAL. But, besides influencing the default for
wal_buffers, a larger shared_buffers doesn't change the amount of
synchronous writes.

Greetings,

Andres Freund

--
 Andres Freund                       http://www.2ndQuadrant.com/
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