Messages in this thread | | | Date | Wed, 30 Sep 2009 12:00:59 +0200 | From | Joerg Roedel <> | Subject | Re: [PATCH] Option to synchronize P-states for AMD family 0xf |
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On Tue, Sep 29, 2009 at 04:23:55PM -0500, Mark Langsdorf wrote:
> AMD Family 0xf processors (Athlon 64s and Opterons) do not > have P-State or C-State invariant TSCs. Instead, the TSC > increments at the current processor frequency, which makes > it unstable and unreliable if cpufreq is enabled. > > This patch introduces a new command parameter for the > PowerNow! driver called "tscsync". When tscsync is > set to 1, the driver forces all processors in the system > to change frequency as the same time to the same frequency. > This unified change means that all the TSCs in the system > increment at the same rate.
Cool feature. Does Linux consider the TSC as stable on these machines even after a longer uptime (say after a week)?
Joerg
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