The latest kernel update, 2.6.32-25-generic, has changed things a bit. At least in my case. Granted, I have changed some things to prevent cpu wakeups by adding hpet=force nohz=off highres=off to the GRUB CMDLINE since the kernel update 2.6.32-24 update. At that time Load Balancing ticks were still appearing, even when idle. With the 2.6.32-25 update there are wakeups but under a different name: [Rescheduling interrupts] <kernel IPI>. What is more surprising is that the wakeups are not appearing while idle which they were with the 2.6.32-24 and others before.
I use a selfmade powersaving script but tested wakeups in Powertop before I activated the script and here are the results. NB! I have turned off some services. This was done on a desktop C2D E6550 with Lucid installed.
When idle (no mouse movement or anything):
Wakeups-from-idle per second : 7,6 interval: 10,0s
no ACPI power usage estimate available
The latest kernel update, 2.6.32-25-generic, has changed things a bit. At least in my case. Granted, I have changed some things to prevent cpu wakeups by adding hpet=force nohz=off highres=off to the GRUB CMDLINE since the kernel update 2.6.32-24 update. At that time Load Balancing ticks were still appearing, even when idle. With the 2.6.32-25 update there are wakeups but under a different name: [Rescheduling interrupts] <kernel IPI>. What is more surprising is that the wakeups are not appearing while idle which they were with the 2.6.32-24 and others before.
I use a selfmade powersaving script but tested wakeups in Powertop before I activated the script and here are the results. NB! I have turned off some services. This was done on a desktop C2D E6550 with Lucid installed.
When idle (no mouse movement or anything):
Wakeups-from-idle per second : 7,6 interval: 10,0s
no ACPI power usage estimate available
Top causes for wakeups: poll_rh_ status (rh_timer_func) watchdog (clocksource_ watchdog) rt_period_ timer)
30,5% ( 4,0) [kernel core] usb_hcd_
15,3% ( 2,0) [kernel core] clocksource_
7,6% ( 1,0) [uhci_hcd:usb3, nvidia] <interrupt>
7,6% ( 1,0) gvfs-afc-volume
7,6% ( 1,0) [kernel core] nv_kern_rc_timer (nv_kern_rc_timer)
3,1% ( 0,4) nautilus
2,3% ( 0,3) clock-applet
2,3% ( 0,3) gnome-panel
2,3% ( 0,3) gedit
1,5% ( 0,2) rtkit-daemon
1,5% ( 0,2) [kernel core] inc_rt_group (sched_
1,5% ( 0,2) gnome-terminal
1,5% ( 0,2) gnome-settings-
Here is when watching a HD movie:
Wakeups-from-idle per second : 150,8 interval: 10,0s
no ACPI power usage estimate available
Top causes for wakeups: poll_rh_ status (rh_timer_func) watchdog (clocksource_ watchdog) rt_period_ timer)
42,3% (126,7) [ata_piix, ata_piix, HDA Intel] <interrupt>
20,9% ( 62,5) [Rescheduling interrupts] <kernel IPI>
16,4% ( 49,0) [uhci_hcd:usb3, nvidia] <interrupt>
8,5% ( 25,6) gnome-mplayer
8,1% ( 24,4) mplayer
1,3% ( 4,0) [kernel core] usb_hcd_
0,7% ( 2,0) [kernel core] clocksource_
0,3% ( 1,0) [kernel core] inc_rt_group (sched_
0,3% ( 1,0) gvfs-afc-volume
0,3% ( 1,0) [kernel core] nv_kern_rc_timer (nv_kern_rc_timer)
0,1% ( 0,3) gnome-terminal
0,1% ( 0,3) gedit
0,1% ( 0,3) gnome-settings-
0,1% ( 0,3) clock-applet
0,1% ( 0,3) gnome-panel
0,1% ( 0,2) rtkit-daemon