Re: [RFC PATCH] x86 alternatives : fix LOCK_PREFIX race with preemptiblekernel and CPU hotplug

[H. Peter Anvin]

Jeremy Fitzhardinge wrote:
> > Xeon 2.0GHz
> >
> >
> > Summary
> >
> >                   no lock prefix (s)   with lock prefix (s)    Speedup
> > make -j1 kernel/      33.94 +/- 0.07         34.91 +/- 0.27      2.8 %
> > hackbench 50           2.99 +/- 0.01          3.74 +/- 0.01     25.1 %
> >   
>
> Yeah, that's more severe than I would have expected.  Perhaps I have AMD 
> numbers in my head.

He doesn't specify what kind of Xeon it is (there are three completely 
different CPUs under the Xeon brand name: P3 Xeon, P4 Xeon, and Core 2 
Xeon), but I think it's a P4 Xeon.

Netburst sucked in so many ways, and this is one of them.

	-hpa


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