Help with improving mysql performance on 6.2PRE

Kris Kennaway kris at
Fri Oct 13 13:13:59 PDT 2006

On Fri, Oct 13, 2006 at 11:49:04AM -0700, Chuck Swiger wrote:
> On Oct 13, 2006, at 11:26 AM, Eric Hodel wrote:
> >>>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?
> The problem of the TSC clocks getting out of sync affects pretty much  
> all AMD X2 dual-core CPUs, as well as the older 32-bit Althon MP  
> CPUs; the Intel Xeon and Core Duo CPUs seem to do a lot better,  
> although older Intel CPUs have also been reported to show problems  
> with the TSC.
> Disabling the fancy power-management capabilities (SpeedStep,  
> PowerNow, Cool-n-quiet) to prevent the system from adjusting the CPU  
> clock frequencies seems to reduce the extent of the problem.   
> However, if you want your system clock to work reliably, using the  
> ACPI-safe or i8254 timecounters is going to do much better than using  
> the faster-but-unreliable TSC method.

Beyond that, just see if it works ;-)

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