Description of problem: The information under /proc/acpi/processor/CPU?/throttling seems odd. First, the CPU never seemed to enter even C1. [Normally, I'd expect to see it in C1 some of the time, I have to boot nohz=off because of another bug: see Bug 443155] This is probably why the system is idling a good few degrees higher under this kernel. Throttling seems different as well. Under kernel-2.6.24.7-92.fc8, CPU0/throttling would be: Could not determine current throttling state. but CPU1/throttling had: state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 88% T2: 75% T3: 63% T4: 50% T5: 38% T6: 25% T7: 13% Under 2.6.25.4-10.fc8, CPU0/throttling is now like CPU1 EXCEPT the asterisk is stuck on the T3 state. Version-Release number of selected component (if applicable): kernel-2.6.25.4-10.fc8 How reproducible: Always. Steps to Reproduce: 1. Boot. Additional info: For acpidump, see bug 448150.
Same with kernel-2.6.25.4-14.fc8, eats battery.
Enters C-states when I remove "nohz=off" with kernel-2.6.25.6-24.fc8, but throttling oddness remains and still seems to run hotter than kernel-2.6.24.7-92.fc8.
Things still seem odd with kernel-2.6.25.6-27.fc8. powertop reports a few hundred wakeups per second here and the processor spending a good amount of time in C3 (but perhaps this is not what the hardware is *actually* doing), so nothing unusual there... but sometimes powertop reports garbage (e.g., tens of thousands --- or even a negative number --- of wups) and the sysfs counts for C-state usage seem to reset every so often.
Even odder in kernel-2.6.25.9-37.fc8, throttling for both cores seems suck in T8.
Back to same throttling strangeness as 2.6.25.4-10.fc8 with kernel-2.6.25.12-62.fc8 (see opening comment). kernel-2.6.24.7-92.fc8 runs cooler on this machine with "nohz=off" than 2.6.25.4-10.fc8 in tickless mode.
Still present in kernel-2.6.26.3-14.fc8.
Appears to be fixed in kernel-2.6.27.5-32.fc9.x86_64, until a suspend/resume cycle. Will report a new bug.