PowerTOP 1.11   (C) 2007, 2008 Intel Corporation 

Collecting data for 15 seconds 


< Detailed C-state information is not available.>
P-states (frequencies)
Wakeups-from-idle per second : 38.7	interval: 15.0s
Top causes for wakeups:
  86.2% ( 32.5)       <interrupt> : extra timer interrupt 
   6.2% (  2.3)     <kernel core> : hrtimer_start (tick_sched_timer) 
   5.1% (  1.9)     <kernel core> : clocksource_watchdog (clocksource_watchdog) 
   0.9% (  0.3)     <kernel core> : hrtimer_start_range_ns (tick_sched_timer) 
   0.7% (  0.3)       <interrupt> : ata_piix 
   0.4% (  0.1)       bdi-default : bdi_forker_task (process_timeout) 
   0.4% (  0.1)         flush-8:0 : bdi_writeback_task (process_timeout) 
   0.2% (  0.1)     <kernel core> : run_timer_softirq (sync_supers_timer_fn) 

Suggestion: increase the VM dirty writeback time from 5.00 to 15 seconds with:
  echo 1500 > /proc/sys/vm/dirty_writeback_centisecs 
This wakes the disk up less frequently for background VM activity

Recent USB suspend statistics
Active  Device name