sure B<cpufreqd> (L<http://cpufreqd.sourceforge.net/>) or a similar tool is
installed and an "cpu governor" (that's a kernel module) is loaded.
+=head2 Plugin C<cpusleep>
+
+This plugin doesn't have any options. It reads CLOCK_BOOTTIME and
+CLOCK_MONOTONIC and reports the difference between these clocks. Since
+BOOTTIME clock increments while device is suspended and MONOTONIC
+clock does not, the derivative of the difference between these clocks
+gives the relative amount of time the device has spent in suspend
+state. The recorded value is in milliseconds of sleep per seconds of
+wall clock.
+
=head2 Plugin C<csv>
=over 4