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Date: Wed, 27 Feb 2013 19:43:02 -0600
From: Joshua Isom <jrisom@gmail.com>
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Subject: Re: Performance Related Question
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On 2/27/2013 4:53 PM, Michael Ross wrote:
>      On a multi-CPU machine using an SMP configured kernel, try values
> between 6 and 10 and see how they speed things up.
>

But you also do need to consider memory usage.  On the areas of 
buildworld that are CPU intensive, they can also be memory intensive. 
If the active processes need to get swapped out to disk, you can wipe 
out any performance gain.  I've noticed this some with clang.  I don't 
care that clang uses more memory, "compile once, run many", but be aware 
of it if you're benchmarking.  The ram amount can also influence cache 
sizes, and you have a major difference in memory amounts.