Re: Solaris and effective_cache_size

On Fri, Feb 15, 2002 at 11:17:42AM -0500, Tom Lane wrote:

> Actually, the default 1000 setting is probably very much on the low side
> --- that's only equivalent to 8 meg of disk cache space after all, and
> on any reasonably modern box there's probably lots more RAM than that
> being used for disk cache.

Yes, that's why I started playing with it.  But performance degrades
again if you raise it too much.  I've had similar results with our
own application.

> However, I'm quite surprised to hear that tweaking effective_cache_size
> affects pgbench results at all.  I'd have thought that all the queries
> used by pgbench would be indexscans anyway...

I was sort of surprised by that, too.  But the effect is totally
consistent over dozens of tests.

A

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