From: Chris Browne <cbbrowne@acm.org>
Subject: Re: Status of Opteron vs Xeon
Date: Fri, 07 Oct 2005 13:33:28 -0400
Organization: cbbrowne Computing Inc
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jeff@frostconsultingllc.com (Jeff Frost) writes:
> What's the current status of how much faster the Opteron is compared
> to the Xeons?  I know the Opterons used to be close to 2x faster,
> but is that still the case?  I understand much work has been done to
> reduce the contect switching storms on the Xeon architecture, is
> this correct?

Work has gone into 8.1 to try to help with the context switch storms;
that doesn't affect previous versions.

Furthermore, it does not do anything to address the consideration that
memory access on Opterons seem to be intrinsically faster than on Xeon
due to differences in the memory bus architecture.  

The only evident ways to address that are:
 a) For Intel to deploy chips with better memory buses;
 b) For Intel to convince people to deploy compilers that 
    optimize badly on AMD to make Intel chips look better...
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