power management regression in linux 3.10?
Hello,
I am using an IBM ThinkPad T60 (i915, Core 2 Duo T7200) and recently upgraded from a custom 3.7 kernel to a custom 3.10-rc4 kernel (v3.10-rc4-1-gc026d8e).
After upgrading, I get around 17-20W power usage instead of 12-15W power usage as I had with 3.7. powertop show that CPU0 is in state POLL all of the idle time, while CPU1 correctly enters C3.
As this may be caused by my kernel configuration, I pastebinned my .config to http://pastebin.ca/2388457. Note that I am using CONFIG_NO_HZ_FULL, which might be nonstandard and actually not sensible for a standard single-user laptop system with GUI.
Do you want me to try something to debug the problem?
Regards,
Michael Karcher
Quoted 9 lines · Michael Karcher
Hello,
I am using an IBM ThinkPad T60 (i915, Core 2 Duo T7200) and recently upgraded from a custom 3.7 kernel to a custom 3.10-rc4 kernel (v3.10-rc4-1-gc026d8e).
After upgrading, I get around 17-20W power usage instead of 12-15W power usage as I had with 3.7. powertop show that CPU0 is in state POLL all of the idle time, while CPU1 correctly enters C3.
Quoted 6 lines
As this may be caused by my kernel configuration, I pastebinned my .config to http://pastebin.ca/2388457. Note that I am using
CONFIG_NO_HZ_FULL, which might be nonstandard and actually not sensible for a standard single-user laptop system with GUI.Do you want me to try something to debug the problem?
Yes, please try with CONFIG_NO_HZ_IDLE and see if you can reproduce the problem.
Does your system use intel_idle? You've set that in .config, but can you check what dmesg says, please?
Rafael
Signature · 2 lines
I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.
Quoted 17 lines · Rafael J. Wysocki
Quoted 9 lines · Michael Karcher
Hello,
I am using an IBM ThinkPad T60 (i915, Core 2 Duo T7200) and recently upgraded from a custom 3.7 kernel to a custom 3.10-rc4 kernel (v3.10-rc4-1-gc026d8e).
After upgrading, I get around 17-20W power usage instead of 12-15W power usage as I had with 3.7. powertop show that CPU0 is in state POLL all of the idle time, while CPU1 correctly enters C3.Quoted 6 lines
As this may be caused by my kernel configuration, I pastebinned my .config to http://pastebin.ca/2388457. Note that I am using
CONFIG_NO_HZ_FULL, which might be nonstandard and actually not sensible for a standard single-user laptop system with GUI.Do you want me to try something to debug the problem?
Quoted 9 lines
Yes, please try with
CONFIG_NO_HZ_IDLEand see if you can reproduce the problem.Does your system use
intel_idle? You've set that in .config, but can you check what dmesg says, please?Rafael
Unset CONFIG_NO_HZ it is setting CONFIG_CPU_IDLE_GOV_MENU which with CONFIG_NO_HZ_FULL set is confusing intel_pstate. I am still trying to figure out what the root cause is commit 5811d996 seems to be implicated.
--Dirk
Quoted 24 lines · Dirk Brandewie
Quoted 23 lines · Rafael J. Wysocki
Quoted 9 lines · Michael Karcher
Hello,
I am using an IBM ThinkPad T60 (i915, Core 2 Duo T7200) and recently upgraded from a custom 3.7 kernel to a custom 3.10-rc4 kernel (v3.10-rc4-1-gc026d8e).
After upgrading, I get around 17-20W power usage instead of 12-15W power usage as I had with 3.7. powertop show that CPU0 is in state POLL all of the idle time, while CPU1 correctly enters C3.Quoted 6 lines
As this may be caused by my kernel configuration, I pastebinned my .config to http://pastebin.ca/2388457. Note that I am using
CONFIG_NO_HZ_FULL, which might be nonstandard and actually not sensible for a standard single-user laptop system with GUI.Do you want me to try something to debug the problem?
Yes, please try with
CONFIG_NO_HZ_IDLEand see if you can reproduce the problem.Does your system use
intel_idle? You've set that in .config, but can you check what dmesg says, please?
Quoted 7 lines
Quoted 3 lines
Rafael
Unset
CONFIG_NO_HZit is settingCONFIG_CPU_IDLE_GOV_MENUwhich withCONFIG_NO_HZ_FULLset is confusingintel_pstate. I am still trying to figure out what the root cause is commit5811d996seems to be implicated.
Well, what about CCing the author (done now)?
Rafael
Quoted 11 lines · Rafael J. Wysocki
Quoted 10 lines · Dirk Brandewie
Quoted 9 lines · Rafael J. Wysocki
Quoted 8 lines · Michael Karcher
Hello,
I am using an IBM ThinkPad T60 (i915, Core 2 Duo T7200) and recently upgraded from a custom 3.7 kernel to a custom 3.10-rc4 kernel (v3.10-rc4-1-gc026d8e).
After upgrading, I get around 17-20W power usage instead of 12-15W power usage as I had with 3.7. powertop show that CPU0 is in state POLL all of the idle time, while CPU1 correctly enters C3.
With CONFIG_NO_HZ_FULL it is expected that CPU 0 consumes more power because it handles the timekeeping for every other CPUs and so it never stop its tick. Paul McKenney is working on a solution to solve that.
But if you see something similar on the other CPUs it's a bug.
Thanks.
Am Montag, den 03.06.2013, 12:37 -0700 schrieb Dirk Brandewie:
Quoted 5 lines · Rafael J. Wysocki
Quoted 4 lines · Michael Karcher
Quoted 1 line
Hello,
Yes, please try with
CONFIG_NO_HZ_IDLEand see if you can reproduce the problem.
Instead of doing that, I successfully applied Dirk's suggestion. Is CONFIG_NO_HZ + CONFIG_NO_HZ_IDLE worth testing?
Quoted 2 lines
Quoted 2 lines
Does your system use
intel_idle? You've set that in .config, but can you check what dmesg says, please?
No, intel_idle complains it doesn't support my CPU family.
Quoted 3 lines
Unset
CONFIG_NO_HZit is settingCONFIG_CPU_IDLE_GOV_MENUwhich withCONFIG_NO_HZ_FULLset is confusingintel_pstate. I am still trying to figure out what the root cause is commit5811d996seems to be implicated.
Unsetting CONFIG_NO_HZ helped. Now CPU0 is using C states again.
Quoted 1 line
--Dirk
Regards,
Michael Karcher
Re: power management regression in linux 3.10? (related to CONFIG_NO_HZ_FULL)
Quoted 8 lines · Michael Karcher
Am Montag, den 03.06.2013, 12:37 -0700 schrieb Dirk Brandewie:
Quoted 5 lines · Rafael J. Wysocki
Quoted 4 lines · Michael Karcher
Quoted 1 line
Hello,
Yes, please try with
CONFIG_NO_HZ_IDLEand see if you can reproduce the problem.Instead of doing that, I successfully applied Dirk's suggestion. Is
CONFIG_NO_HZ+CONFIG_NO_HZ_IDLEworth testing?
Yes, it is.
Quoted 3 lines
Quoted 2 lines
Quoted 2 lines
Does your system use
intel_idle? You've set that in .config, but can you check what dmesg says, please?No,
intel_idlecomplains it doesn't support my CPU family.
I thought so. It is using the ACPI idle driver, then, so I think cpuidle in general is affected.
That seems to be a time accounting problem of some sort (adding CCs to Ingo and Thomas).
Thanks,
Rafael
Signature · 2 lines
I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.