Re: Need help with 8.4 Performance Testing

On Tue, 2008-12-09 at 10:21 -0700, Scott Marlowe wrote:
> On Tue, Dec 9, 2008 at 9:37 AM, Scott Carey <scott@richrelevance.com> wrote:

> Lucky you, having needs that are fulfilled by sequential reads.  :)
>
> I wonder how many hard drives it would take to be CPU bound on random
> access patterns?  About 40 to 60?  And probably 15k / SAS drives to
> boot.  Cause that's what we're looking at in the next few years where
> I work.

I was able to achieve only 10-20% IO/Wait even after beating the heck
out of the machine with 50 spindles (of course it does have 16 CPUs):


http://www.commandprompt.com/blogs/joshua_drake/2008/04/is_that_performance_i_smell_ext2_vs_ext3_on_50_spindles_testing_for_postgresql/


>
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