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— | cpufreq [2013/04/10 17:03] (current) – created - external edit 127.0.0.1 | ||
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+ | ======= cpufreq ======= | ||
+ | ===== Synopsis ====== | ||
+ | < | ||
+ | ====== Intro ====== | ||
+ | |||
+ | < | ||
+ | |||
+ | ====== cpufreq ====== | ||
+ | |||
+ | To control the cpustate you need to load the [[http:// | ||
+ | NOTE: You cannot load kernel modules if in securelevel 1 or above, see below on how to enable the kernel module on the next reboot. | ||
+ | |||
+ | You can check if the module is loaded by using the kldstat utility | ||
+ | |||
+ | Output of kldstat should be something like this. | ||
+ | |||
+ | < | ||
+ | Id Refs Address | ||
+ | | ||
+ | | ||
+ | </ | ||
+ | |||
+ | This will however only work until the next reboot, so you want to add the following line to / | ||
+ | < | ||
+ | cpufreq_load=" | ||
+ | </ | ||
+ | |||
+ | This will allow you to view and set the CPU Frequency manually. | ||
+ | |||
+ | This is done via the following sysctl' | ||
+ | |||
+ | | dev.cpu.n.freq | The Current CPU Frequency in MHz ((n is the CPU number (starting at 0))). | ||
+ | | dev.cpu.n.freq_levels | CPU Frequency levels available in MHz/mW ((milliwatts)). | | ||
+ | |||
+ | On some systems the latter part may be -1 for undefined. | ||
+ | ====== Sample ====== | ||
+ | |||
+ | Pentium 4 2.8 GHz | ||
+ | < | ||
+ | $ sysctl dev.cpu.0.freq dev.cpu.0.freq_levels | ||
+ | dev.cpu.0.freq: | ||
+ | dev.cpu.0.freq_levels: | ||
+ | </ | ||
+ | |||
+ | ====== Setting CPU speed ====== | ||
+ | |||
+ | dev.cpu.0.freq can be used to view and/or set the current CPU speed, to view the cpuspeed just run sysctl dev.cpu.0.freq, | ||
+ | |||
+ | ====== Using powerd ====== | ||
+ | |||
+ | You can use powerd(8) to control the CPU speed automatically, | ||
+ | |||
+ | insert the following line into ''/ | ||
+ | <file txt rc.conf> | ||
+ | powerd_enable=" | ||
+ | </ | ||
+ | |||
+ | Next, run ''/ | ||
+ | Example: | ||
+ | |||
+ | < | ||
+ | # ps -ax |grep powerd | ||
+ | | ||
+ | </ | ||
+ | |||
+ | ====== Verifying the CPU Speed ====== | ||
+ | |||
+ | You can now see the CPU speed constantly changing with the load of the machine by monitoring dev.cpu.n.freq sysctl. |