Currently the XFCE4 CPUFreq plugin uses a poll-based method via a timeout to update its status. This is very inefficient  and can cause unnecessary CPU load. Please you use an event-based method like libevent .
(This bug report does not refer to cpugraph, but there is no component entry for cpufreq.)
(In reply to comment #0)
> (This bug report does not refer to cpugraph, but there is no component entry
> for cpufreq.)
The cpufreq component has been added now
The plugin still uses polling, however only every second or in larger intervals. I don't think there would be any benefit now in using libevent? Besides, those events might fire even more often than every second. I'm closing this bug, if you're still watching this feel free to reopen and explain.