Re: [PATCH] add a clear_pages function to clear pages of higher order

From: Christoph Lameter <clameter_at_sgi.com>
Date: 2005-03-19 02:00:06
On Fri, 18 Mar 2005, Denis Vlasenko wrote:

> NT stores are not about 5% increase. 200%-300%. Provided you are ok with
> the fact that zeroed page ends up evicted from cache. Luckily, this is exactly
> what you want with prezeroing.

These are pretty significant results. Maybe its best to use non-temporal
stores in general for clearing pages? I checked and Itanium has always
used non-temporal stores. So there will be no benefit for us from this
approach (we have 16k and 64k page sizes which may make the situation a
bit different). Try to update the i386 architectures to do the same?

Or for prezeroing, you could register a zeroing driver that would use the
non-temporal stores with V8 of the prezeroing patches. In any case the
clear_pages patch is not useful the way it was intended for us and I am
have dropped this from the prezeroing patch.

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Received on Fri Mar 18 10:01:13 2005

This archive was generated by hypermail 2.1.8 : 2005-08-02 09:20:37 EST