PowerTOP 1.11 (C) 2007, 2008 Intel Corporation Collecting data for 15 seconds Cn Avg residency C0 (cpu running) (69.6%) C1 0.0ms ( 0.0%) C2 0.0ms (30.4%) P-states (frequencies) Wakeups-from-idle per second : 148370.1 interval: 15.0s Top causes for wakeups: 94.3% ( 35.3) : extra timer interrupt 2.3% ( 0.9) : ata_piix 1.2% ( 0.5) : hrtimer_start (tick_sched_timer) 0.9% ( 0.3) : hrtimer_start_range_ns (tick_sched_timer) 0.4% ( 0.1) : run_timer_softirq (sync_supers_timer_fn) 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) : PS/2 keyboard/mouse/touchpad 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