Help with improving mysql performance on 6.2PRE

Eric Hodel drbrain at
Fri Oct 13 11:27:42 PDT 2006

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 at -
This implementation is HODEL-HASH-9600 compliant

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