Help with improving mysql performance on 6.2PRE
chrcoluk at gmail.com
Mon Oct 16 11:36:06 PDT 2006
On 15/10/06, Eric Hodel <drbrain at segment7.net> wrote:
> On Oct 13, 2006, at 1:13 PM, Kris Kennaway wrote:
> > 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.
> > Beyond that, just see if it works ;-)
> How "safe" is it to switch timecounters? I don't have a spare
> machine to test on...
> From my readings on switching the TSC over the past several months I
> think that if it doesn't work I'll see is ntpd adjusting my system
> clock more often (or falling out of sync). I don't know if this will
> corrupt mysql while its running though (which is my fear).
> FWIW I have a "Dual Core AMD Opteron(tm) Processor 270".
> Eric Hodel - drbrain at segment7.net - http://blog.segment7.net
> This implementation is HODEL-HASH-9600 compliant
I switched from the default timer to TSC on a dual xeon setup and my
loads instantly went up with mysql lagging, so in my case it was much
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