Re: Dynamic configure max_cstate

From: Len Brown
Date: Tue Jul 28 2009 - 15:25:32 EST



> Entering a deep C state can cause strange things to timers: some of
> them, especially tsc, become unreliable.

The Nehalem family CPU has a non-stop constant-frequency TSC.

The measurements that Yanmin quotes show that the TSC
is the lowest overhead timesource in the system.

thanks,
Len Brown, Intel Open Source Technology Center
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