From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: Latest unstable detects cpu speed incorrectly
Date: Tue, 27 Oct 2009 12:46:41 -0700
Message-ID: <4AE74E21.5050407@goop.org>
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To: Valtteri Kiviniemi <valtteri.kiviniemi@dataproof.fi>
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On 10/27/09 09:36, Valtteri Kiviniemi wrote:
> Hi,
>
> I also noticed that I dont have "[ ]     Paravirtualization layer for
> spinlocks" enabled in kernel. Should that be enabled?

It's not required.  It may help overall system load on loaded systems
(where there are consistently more runnable vcpus than pcpus), but it
can also slow things down.  I generally recommend turning it off on
problematic systems in order to simplify things (there have been bugs in
that code in the past, and its all fairly subtle).

    J