Comment 1 for bug 290095

bump, seconded.

Powertop is a *very* handy tool, esp. for a laptop, and setting that kernel option carries very low risk of something stopping to work and has the benefit of changing the PT output from the stuff quoted above to something like this (from another machine), which is much more useful:

[...]
Top causes for wakeups:
  35.2% (206.2) java : futex_wait (hrtimer_wakeup)
  19.9% (116.4) <interrupt> : ide0
  13.6% ( 79.4) <kernel core> : ide_do_rw_disk (ledtrig_ide_timerfunc)
  13.5% ( 79.0) java : schedule_timeout (process_timeout)
  10.2% ( 60.0) <interrupt> : ATI IXP, fglrx[0]@PCI:1:5:0
   2.8% ( 16.2) <interrupt> : b43
   1.6% ( 9.6) porthole : schedule_timeout (process_timeout)
   0.6% ( 3.8) <interrupt> : ohci_hcd:usb1, ohci_hcd:usb2
   0.6% ( 3.8) USB device 2-3 : PS/2+USB Mouse ()
   0.3% ( 2.0) kded : futex_wait (hrtimer_wakeup)
[...]