Hi,
On 7/9/20 2:31 PM, Hans de Goede wrote:
Hi,
On 7/7/20 5:43 PM, Rafael J. Wysocki wrote:
Hi Hans,
On Tue, Jul 7, 2020 at 5:32 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
Hi Rafael,
I got a copy of the below bugreport in my mailbox and I
was wondering if this rings any bells.
Are there any relevant power-management / scheduler
changes in 5.7 (vs 5.6) which might be related?
There were a few, but I'm not sure how they can cause thermal issues to happen.
And is there any quick way for the reporter to test this
(by e.g. picking a different scheduler / cpufreq-governor).
Well, as usual, I would recommend looking for possible configuration
differences between the good and bad cases, ie. different default
governors, different cpufreq/cpuidle drivers etc.
Also, if the system is Intel-based, run turbostat to collect CPU PM
information for both the good and bad cases.
Ok I've asked the user to run some tests and provide powertop
and turbostat outputs for both the cold and hot cases.
I will follow-up on this when I know more.
Ok, I've asked the user to gather the necessary info. He has collected
screenshots from both powertop and turbostat under both 5.6 (with the
CPU staying cool) and with 5.7 (where the CPU runs a bit hot) both with
the system fully idle.
The screenshots are attached to the bug as a tarbal:
https://bugzilla.redhat.com/show_bug.cgi?id=1854502
I've never looked at turbostat output before so I do not know what
I'm looking for there. But the powertop output does show a significant
difference.
On the powertop overview page we can see that 5.7 has slightly less
wakeup then 5.6 (probably just normal variation) but despite this,
the "idle stats" page shows that under 5.6 we get 90/91% C7 residency,
where as 5.7 only reaches 85%, that seems like a significant difference
to me. IOW the CPU is in a higher powerstae (consuming more power) for
15% of the time with 5.6, vs 10% with 5.7.
Note that this users system is somewhat customized, he is using
bumblebee with the nvidia binary driver to run games, while
using the i915 gfx for his normal desktop stuff. Doing his
tests no apps are running using the nvidia GPU and in both
cases the nvidia GPU is powered-down (according to the /proc/...
info).
He is also using TLP and some utility to undervolt the GPU. None
of this seems to explain the C7 residency difference though, so
despite his non-standard setup it would be good (IMHO) to still
see if we can try to root-cause that.
Regards,
Hans
-------- Forwarded Message --------
Subject: [Bug 1854502] New: Noticeably Increased CPU temperature
Date: Tue, 07 Jul 2020 15:23:38 +0000
From: bugzilla@xxxxxxxxxx
To: hdegoede@xxxxxxxxxx
https://bugzilla.redhat.com/show_bug.cgi?id=1854502
Bug ID: 1854502
Summary: Noticeably Increased CPU temperature
Product: Fedora
Version: 32
Hardware: x86_64
OS: Linux
Status: NEW
Component: kernel
Severity: medium
Assignee: kernel-maint@xxxxxxxxxx
Reporter: aria.aghazade@xxxxxxxxx
QA Contact: extras-qa@xxxxxxxxxxxxxxxxx
CC: acaringi@xxxxxxxxxx, airlied@xxxxxxxxxx,
bskeggs@xxxxxxxxxx, hdegoede@xxxxxxxxxx,
ichavero@xxxxxxxxxx, itamar@xxxxxxxxxxxxxxxx,
jarodwilson@xxxxxxxxx, jeremy@xxxxxxxxxx,
jglisse@xxxxxxxxxx, john.j5live@xxxxxxxxx,
jonathan@xxxxxxxxxxxxxx, josef@xxxxxxxxxxxxxx,
kernel-maint@xxxxxxxxxx, lgoncalv@xxxxxxxxxx,
linville@xxxxxxxxxx, masami256@xxxxxxxxx,
mchehab@xxxxxxxxxxxxx, mjg59@xxxxxxxxxxxxx,
steved@xxxxxxxxxx
Target Milestone: ---
Classification: Fedora
First things first, I'm running Fedora 32 with latest packages on intel 6700hq.
With latest kernel-5.7, cpu temperatures are noticeably higher.
Using kernel-5.6 my idle cpu temperature is around 35-40°C, but with kernel-5.7
its around 50-55. Htop and KDE System Monitor don't show anything using cpu and
idle cpu usage on both kernels is 0-2%.
I first noticed this issue on kernel-5.7.6-201.fc32.x86_64, and it is also
there with kernel-5.7.7-200.fc32.x86_64.
Booting with kernel-5.6.19-300.fc32.x86_64 fixes the issue.
Are you running any modules that not shipped with directly Fedora's kernel? No.
