[ltp] X41 power consumption

[Paul Fox]

i can't seem to get below about 14W on my X41 thinkpad.  is this
normal for this model?  there are no X41 numbers listed on the
wiki idle comparison page, but i've been seeing lower numbers
for both T40 and X60 series machines, so i'm curious.


this powertop output is fairly typical.  i can get it down to 13.8 or
so with backlight off.

does anyone know what "extra timer interrupt" means?  i'm running
ubuntu gutsy, and NO_HZ is enabled.

paul

 > 
 > 
 >      PowerTOP version 1.8       (C) 2007 Intel Corporation
 > 
 > Cn                Avg residency       P-states (frequencies)
 > C0 (cpu running)        ( 1.3%)         1.60 Ghz     0.0%
 > C1                0.0ms ( 0.0%)         1500 Mhz     0.0%
 > C2                0.0ms ( 0.0%)         1400 Mhz     0.0%
 > C3                0.0ms ( 0.0%)          600 Mhz   100.0%
 > C4               20.8ms (98.7%)
 > 
 > Wakeups-from-idle per second : 51.1     interval: 15.0s
 > Power usage (ACPI estimate): 14.3W (3.9 hours)
 > 
 > Top causes for wakeups:
 >   51.8% ( 23.5)       <interrupt> : extra timer interrupt
 >   22.3% ( 10.1)       <interrupt> : acpi
 >    4.4% (  2.0)      S20powernowd : queue_delayed_work_on (delayed_work_timer_fn
 >    2.6% (  1.2)        FvwmScript : schedule_timeout (process_timeout)
 >    2.3% (  1.1)              Xorg : do_setitimer (it_real_fn)
 >    2.3% (  1.1)              ntpd : do_setitimer (it_real_fn)
 >    2.2% (  1.0)        FvwmScript : do_nanosleep (hrtimer_wakeup)
 >    2.2% (  1.0)          ifconfig : tg3_open (tg3_timer)
 >    2.2% (  1.0)     <kernel core> : queue_delayed_work_on (delayed_work_timer_fn
 >    2.2% (  1.0)              gpsd : schedule_timeout (process_timeout)
 >    2.2% (  1.0)              Xorg : schedule_timeout (process_timeout)
 >    0.7% (  0.3)   <kernel module> : <f89b6281> (irlmp_discovery_timer_expired)
 >    0.6% (  0.3)     <kernel core> : neigh_table_init_no_netlink (neigh_periodic_
 >    0.6% (  0.3)       firefox-bin : schedule_timeout (process_timeout)
 >    0.4% (  0.2)       firefox-bin : futex_wait (hrtimer_wakeup)
 >    0.3% (  0.1)             cupsd : schedule_timeout (process_timeout)
 >    0.3% (  0.1)   <kernel module> : neigh_table_init_no_netlink (neigh_periodic_
 >    0.1% (  0.1)         ssh-agent : schedule_timeout (process_timeout)
 >    0.1% (  0.1)         ssh-agent : do_setitimer (it_real_fn)



=---------------------
 paul fox, pgf@foxharp.boston.ma.us (arlington, ma, where it's 56.3 degrees)