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wiki:cpu_frequency_scaling_basics [2011/11/20 15:20] – [#GOVERNORS] bmarkuswiki:cpu_frequency_scaling_basics [2014/12/26 06:43] (current) – bmarkus
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 In most cases it works fine and you do not need any additional action. In most cases it works fine and you do not need any additional action.
 +
 +However, as there are certain setups where either not all required drivers are automatically loaded and/or where the 'ondemand' governor gets prevented from being enabled (due to latency being too high), it is a good idea to do a check - based on info which follows - whenever running TC4 for the first time with a specific processor or chipset.
  
  
 ===== #VIEW CPU FREQUENCY INFORMATION ===== ===== #VIEW CPU FREQUENCY INFORMATION =====
  
-If you want to view actual CPU frequency settings, install cpufreq-utils.tcz extension and use command:+If you want to view actual CPU frequency settings, install cpufrequtils.tcz extension and use command:
  
 cpufreq-info cpufreq-info
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 +===== #TROUBLESHOOTING =====
 +
 +The following relates to a Pentium M under TC3.8.4 (2.6.33.3 kernel) running on a Dell Precision M70\\
 +laptop, but may still be applicable if you run into a similiar problem.\\
 +Installed cpufrequtils and selected ondemand govenor. The policy line from the cpufreq-info command read:\\
 +<code>current policy: frequency should be within 800 MHz and 800 MHz.</code>
 +indicated that CPU was locked at 800Mhz. Executing the command:
 +<code>cat /sys/devices/system/cpu/cpu0/cpufreq/bios_limit</code>
 +returned the value 800000 (frequency in Khz). Using the boot code:
 +<code>processor.ignore_ppc=1</code>
 +fixed that. Now bios_limit contains 2267000 (2.267Ghz), the maximum speed for this CPU. Checking\\
 +\proc\cpuinfo several times showed that the frequency was bouncing between 800Mhz and 2.27Ghz\\
 +even though the machine was not doing anything. Changing the governor to conservative fixed that.\\
 +For links to bug reports that helped solve this problem, see:\\
 +http://forum.tinycorelinux.net/index.php/topic,14917.msg85013.html#msg85013
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