On Fri, 2 Jan 2009, Tom Lane wrote:

> ISTM that you *should* be able to see an improvement on even
> single-spindle systems, due to better overlapping of CPU and I/O effort.

The earlier synthetic tests I did:

http://archives.postgresql.org/pgsql-hackers/2008-09/msg01401.php

Showed a substantial speedup even in the single spindle case on a couple 
of systems, but one didn't really seem to benefit.  So we could theorize 
that Robert's test system is more like that one.  If someone can help out 
with making a more formal test case showing this in action, I'll dig into 
the details of what's different between that system and the others.

--
* Greg Smith gsmith(at)gregsmith(dot)com http://www.gregsmith.com Baltimore, MD

In response to

• Re: posix_fadvise v22 at 2009-01-02 15:33:25 from Tom Lane

Responses

• Re: posix_fadvise v22 at 2009-01-02 20:01:45 from Tom Lane
• Re: posix_fadvise v22 at 2009-01-02 20:43:41 from Bruce Momjian

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