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On a 2011 17" MacBook Pro (i7, 10.6, 16GB ram) I do not have any options in the energy saver preference panel to control CPU throttling. I need to be able to disable CPU throttling for short periods of time - or at least force OS X to a certain state and stay there so that I can get consistent results from test to test in a performance comparison situation.

Are there methods or apps that allow me to control the energy saver features and particularly CPU throttling and CPU disabling for recent (sandy bridge) Macs?

CHUD does not appear to support this machine (it doesn't correctly report the CPU type) and while I can manually disable hyperthreading and processor cores using /Library/Application Support/HWPrefs/CPUPalette.app it doesn't give me the option to tell OS X not to throttle anything.

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So maybe you can install one of this Windows tools if you have Boot Camp, VMware or Parallels. Did anyone try this? –  Michael Lehn Oct 5 '12 at 16:13
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2 Answers

up vote 3 down vote accepted

This particular machine is a second generation Core i7, which includes Intel's Turbo Boost technology.

This is, essentially, a power management processor that has the ability to change the clock speed and disable/enable processor cores on the fly. It requires no software intervention, the entire algorithm exists in silicon on the i7 processor itself.

While utilities to control it are starting to appear for windows, Apple doesn't provide a method to disable it, nevermind control it, and I have not yet found any utilities that would allow me to disable or control it on OS X.

So, at this point, the answer is that you cannot disable CPU throttling or power control under OS X for Turbo Boost capable processors - it's all automated inside the processor, and Apple doesn't have a public API to control it.

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sudo pmset -a dps 0

This is supposed to disable or enable dynamic processor speed changes.

Also, there is a kernel ext you can remove off your system (copy to a thumb drive etc) that is responsible for this behavior I believe. It is IOPlatformPluginFamily.kext in the /library/extensions folder. Replace when you're done; you don't want to remove it permanantly.

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if not a i3/i5/i7 coolbook.se/CoolBook.html is good too –  TheIrishGuy Feb 20 '12 at 17:03
    
pmset does not appear to have an option for dps on this macbook pro. It returns with usage instructions: $ sudo pmset -a dps 0 - Usage: pmset <options> - See pmset(1) for details: 'man pmset'. A pmset -g live does not show the dps option at all, nor any option that suggests CPU throttling control. –  Adam Davis Feb 20 '12 at 17:14
    
Well the cpu throttles itself based on tempature. The safest and easiest solution based on this evidence is SMC fan control, turn up your fans, they'll be loud, and watch for any cpu speed changes. Forgive my past answers, I glazed over the i7 fact. –  TheIrishGuy Feb 20 '12 at 17:21
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