New: 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
http://bugzilla.kernel.org/show_bug.cgi?id=11170
Summary: 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
Product: Power Management
Version: 2.5
KernelVersion: 2.6.25.12-62.fc8
Platform: All
OS/Version: Linux
Tree: Fedora
Status: NEW
Severity: normal
Priority: P1
Component: cpufreq
AssignedTo: [email protected]
ReportedBy: [email protected]
Latest working kernel version: 2.6.24.7-92.fc8
Earliest failing kernel version: 2.6.25
Distribution: Fedora 8
Hardware Environment: Intel Core 2 Duo T8100 on Clevo M720R notebook
Software Environment: i686
Problem Description:
Kernel 2.6.24.7 runs cooler on this machine, even when booted "nohz=off", than Kernel 2.6.25.* in tickless mode. The difference, in both coretemp and ACPI thermal zone, is typically 4-6 C. This is all the more odd since 2.6.25 seems to better support ACPI features like the lid and sleep button, which were detected under 2.6.24 but didn't generate events, and the "smart power" button which limits the clock to 1.2 GHz. [I'm booting "nohz=off" due to another problem whereby the machine seems to "pause" (*not* freeze) when there are few interrupts happening.]
Under 2.6.24.7, powertop reports 100% "C0 (cpu running)" residency, just altering the clock rate, and around 100-200 wups. With 2.6.25.12, it shows two C0 states, "C0 (cpu running)" and just "C0"; the residency figures don't make much sense, and I suspect powertop is reporting garbage in both cases (sometimes things like 8 wups). Furthermore, I don't really understand what I see in /proc/acpi/processor/*/power --- with 2.6.24.7, only C1 shows any usage, and the number keeps resetting after a few seconds. With 2.6.25.12, C1--C3 show some usage, again with the numbers resetting.
Another thing (I don't know if it's related) is that under 2.6.25.12, I get the following in dmesg:
ACPI Exception (thermal-0457): AE_ERROR, ACPI thermal trip point state
changed
I also see a lot of
ACPI: Invalid passive threshold
in dmesg for 2.6.24.7 if I cold-boot 2.6.25.12 first. Furthermore, cold-booting 2.6.25.12 and then re-booting into 2.6.24.7 makes the lid work under the latter.
Signature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
[Bug 11170] 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
http://bugzilla.kernel.org/show_bug.cgi?id=11170
[email protected] changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |[email protected] Regression|0 |1
Signature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
[Bug 11170] 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
In reply to [email protected]http://bugzilla.kernel.org/show_bug.cgi?id=11170
[email protected] changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |[email protected], | |[email protected]
------- Comment #1 from [email protected] 2008-07-28 03:56 ------- Please provide acpidump and dmesg.
This should be assigned to the ACPI and not Power Management component. I cannot change it.
Signature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
[Bug 11170] 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
In reply to [email protected]http://bugzilla.kernel.org/show_bug.cgi?id=11170
------- Comment #2 from [email protected] 2008-07-30 06:35 ------- Created an attachment (id=17030)
--> (http://bugzilla.kernel.org/attachment.cgi?id=17030&action=view)
acpidump output for this machine
Signature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
[Bug 11170] 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
In reply to [email protected]http://bugzilla.kernel.org/show_bug.cgi?id=11170
------- Comment #3 from [email protected] 2008-07-30 06:35 ------- Created an attachment (id=17031)
--> (http://bugzilla.kernel.org/attachment.cgi?id=17031&action=view)
dmesg output with kernel 2.6.24.7-92.fc8
Signature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
[Bug 11170] 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
In reply to [email protected]http://bugzilla.kernel.org/show_bug.cgi?id=11170
[email protected] changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|cpufreq |Power-Processor
Product|Power Management |ACPISignature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
[Bug 11170] 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
In reply to [email protected]***
*** This list is moving to [email protected].
*** Please resubscribe to the new list, and send your message there. Thanks.
***
http://bugzilla.kernel.org/show_bug.cgi?id=11170
------- Comment #4 from [email protected] 2008-08-03 22:58 ------- Will you please attach the following outputs?
acpidump --addr 0x7f6d4e23 --length 0x2A8 -o cpu0ist
acpidump --addr 0x7f6d50cb --length 0xb1 -o cpu1ist
acpidump --addr 0x7f6d48f4 --length 0x4aa -o cpu0cst
acpidump --addr 0x7f6d4d9e --length 0x85 -o cpu1cst Thanks.
Signature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
[Bug 11170] 2.6.24 w/ nohz=off runs cooler than 2.6.25 tickless
In reply to [email protected]***
*** This list is moving to [email protected].
*** Please resubscribe to the new list, and send your message there. Thanks.
***
http://bugzilla.kernel.org/show_bug.cgi?id=11170
[email protected] changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |acpi-
| |[email protected]
| |etSignature · 3 lines
Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.