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Date: Thu, 17 Jul 2008 08:02:45 -0700
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: Peter Zijlstra <peterz@infradead.org>
CC: Ingo Molnar <mingo@elte.hu>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       "Alex Nixon (Intern)" <Alex.Nixon@eu.citrix.com>,
       Ian Campbell <Ian.Campbell@eu.citrix.com>
Subject: Re: Large increase in context switch rate
References: <487E43D9.7080703@goop.org> <1216286250.5232.67.camel@twins>
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Peter Zijlstra wrote:
> Is this specific to Xen?, as a native kernel doesn't do more than ~3k
> cs/s with make -j3 on my dual core.
>   

No, it doesn't seem to be.  A CONFIG_PARAVIRT kernel running on bare 
hardware shows the same context switch rate.  Merely turning 
CONFIG_PARAVIRT on should have no effect on context switch rate (though, 
Alex, it would be worth double-checking, just to be sure).

    J