| Re: [eigen] Performance gap between gcc and msvc ? |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Performance gap between gcc and msvc ?
- From: David Roundy <roundyd@xxxxxxxxxxxxxxxxxxxxxxx>
- Date: Fri, 18 Jun 2010 12:27:22 -0700
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On Fri, Jun 18, 2010 at 12:09 PM, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:
> This smells like code tuned for larger CPU caches than your Core i5 has. Indeed:
> - you are using very large matrices, so it's crucial that blocks fit
> in the cpu caches.
> - Core i5 are mass market cpus with presumably not too big caches.
>
> Try finding out the size of your caces (e.g. cat /proc/cpuinfo on
> linux) and playing with Eigen's cache size settings (see recent thread
> here).
Is this something that could be done automatically at runtime?
David