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From: Eric Hodel <drbrain@segment7.net>
Date: Fri, 13 Oct 2006 11:26:09 -0700
To: Kris Kennaway <kris@obsecurity.org>
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Subject: Re: Help with improving mysql performance on 6.2PRE
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On Oct 12, 2006, at 1:53 PM, Kris Kennaway wrote:
> On Thu, Oct 12, 2006 at 11:25:48AM +0200, Oliver Fromme wrote:
>> Jerry Bell wrote:
>>> I have a Dell PE2950 with 2 dual core 3.73Ghz processors and 4G  
>>> of ram.
>>> [...]
>>> changed the clock to TSC
>>
>> As far as I know, it is unsafe to use TSC on SMP systems.
>>
>> Or did that change recently?
>
> It's only on certain systems, apparently.

Is there a list of systems where it is safe to use the TSC with SMP?   
Or some script we can run?

> Note that you have to enable a second sysctl to allow it to actually
> use TSC on SMP, not just change the preferred timecounter.

-- 
Eric Hodel - drbrain@segment7.net - http://blog.segment7.net
This implementation is HODEL-HASH-9600 compliant

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