There's definitely something funny going on with timers, as the command-line sleep utility seems to sleep much longer than intended, especially if the device is saving power. Verifying with perl sleep: # perl -e 'printf("%d\n", sleep(10));' 117 i.e. a 10 second sleep took 117 seconds of wall clock time. This after disabling tohd to save power. I began to wonder about this when powertop runs never seemed to finish, or even start (preceded by sleep 120...)