[gutsy] powertop reports nearly 1000 wakeups during a package update

[Michael Bienia]

Binary package hint: synaptic

I've run powertop during an update of my gutsy installation.

Powertop reported nearly 1000 wakeups for synaptic during a package update:

  39.3% (932.2) synaptic : do_nanosleep (hrtimer_wakeup)
  38.2% (907.2) gksu : do_nanosleep (hrtimer_wakeup)

This numbers are for synaptic started from the menu and doing a package update as I didn't catch the numbers from the original run.

[Sebastian Heinlein (glatzor)]

And that is bad? I don't have got any numbers to compare to.

[Michael Bienia (geser)]

Without synaptic my notebook has between 100 and 200 wakeups per second. So synaptic alone makes 5 to 10 times more wakeups per second than the sum of the remaining processes.

The powertop website (http://www.linuxpowertop.org/powertop.php) mentions that "When running a full GNOME desktop, 3 wakeups per second is achievable.".
200 wakeups per second is not very good. Creating 1000 wakeups per second from one process is IMHO very bad.

[Mike Dahlgren (dahlgren)]

I don't think a 1000 wakups a second is lot when you're actually doing something. Dynamic ticks only come into play only when the computer is idle, otherwise you want a really high number. That means your cpu is processing a lot of data (could be considered a good thing). This isn't a synaptic issue because you can reach 1000/d-tics/sec though any process that requires the system to respond often (download files, games, play videos). This tool is provided for a benchmark to see what wakes up when the system should be idle. Think about how every time you move your mouse your computer has to calculate its position hundreds of times a second. If you don't believe me watch the powertools while you do just that.

   Thanks,
       ~ Mike

[Sebastian Heinlein (glatzor)]

When installing packages Synaptic is not idle.

Please feel free to reopen the bug if the behavior of an idle Synaptic is bad.

Cheers,

Sebastian