[sles-beta] Intel_Idel - Apci_Idel - Slow Wall Clock time SP1 to SP2 what about SP3?

[Matthias G. Eckermann]

Hello Dick and all,

On 2013-03-14 T 09:55 +0000 Waite, Dick wrote:
 
> Second run with boot parameters set to 
> intel_idle.max_cstate=0 processor.max_cstate=0 idle=mwait
 
> I have a pretty nasty heads-up. If you have
> hardware using an Intel XEON and a newer Linux
> kernel, you may be experiencing very high CPU
> latency.  You can check yourself:
> 
> cat /sys/devices/system/cpu/cpuidle/current_driver
> 
> If it says intel_idle, the Linux kernel will
> *aggressively* put your CPU to sleep. We
> definitely noticed this, and it's pretty darn
> painful. But it's *more* painful in your
> asynchronous, standby, or otherwise less busy
> nodes. Why?
> 
> As you can imagine, the secondary nodes don't get
> much activity, so spend most of their time
> sleeping. Now the CPU has a lot more sleep time,
> and wake latency while trying to copy data or
> process new WAL traffic.

we are aware of this issue and are working on an
analysis together with our hardware partners.

We do not know yet, if this issue can be fixed in
sw, or if requires firmware updates on the hw side.

We will keep you posted.

so long -
	MgE

-- 
Matthias G. Eckermann     Senior Product Manager   SUSE® Linux Enterprise
Phone: +49 30 44315731    Mobile: +49 179 2949448    E-Mail: mge at suse.com
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