- CPU frequency and voltage scaling statictics in the Linux(TM) kernel
+ CPU frequency and voltage scaling statistics in the Linux(TM) kernel
L i n u x c p u f r e q - s t a t s d r i v e r
1. Introduction
-cpufreq-stats is a driver that provices CPU frequency statistics for each CPU.
-This statistics is provided in /sysfs as a bunch of read_only interfaces. This
-interface (when configured) will appear in a seperate directory under cpufreq
+cpufreq-stats is a driver that provides CPU frequency statistics for each CPU.
+These statistics are provided in /sysfs as a bunch of read_only interfaces. This
+interface (when configured) will appear in a separate directory under cpufreq
in /sysfs (<sysfs root>/devices/system/cpu/cpuX/cpufreq/stats/) for each CPU.
Various statistics will form read_only files under this directory.
All the statistics will be from the time the stats driver has been inserted
to the time when a read of a particular statistic is done. Obviously, stats
-driver will not have any information about the the frequcny transitions before
+driver will not have any information about the frequency transitions before
the stats driver insertion.
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This gives the amount of time spent in each of the frequencies supported by
this CPU. The cat output will have "<frequency> <time>" pair in each line, which
will mean this CPU spent <time> usertime units of time at <frequency>. Output
-will have one line for each of the supported freuencies. usertime units here
+will have one line for each of the supported frequencies. usertime units here
is 10mS (similar to other time exported in /proc).
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"CPU frequency translation statistics details" (CONFIG_CPU_FREQ_STAT_DETAILS)
provides fine grained cpufreq stats by trans_table. The reason for having a
-seperate config option for trans_table is:
+separate config option for trans_table is:
- trans_table goes against the traditional /sysfs rule of one value per
interface. It provides a whole bunch of value in a 2 dimensional matrix
form.