How to set intel_idle.max_cstate=1
How can i set intel idle max cstate to 1 and how can i check when it will done. i have a freeze problem because of bay trail cores.
i tried kernel 4.5 4.1.12 4.4 but freeze problem still continue. at the moment 4.4 is my kernel version.
If using GRUB:
With sudo
, edit /etc/default/grub
and edit the GRUB_CMDLINE_LINUX_DEFAULT
line adding intel_idle.max_cstate=1
to whatever might already be there. After saving the file run sudo update-grub
, then re-boot. Suggest that you save a copy of your original grub file first.
To check that your cstate is not going deeper than 1 use turbostat (package: linux-tools-common).
Example (where there is already something on the GRUB_CMDLINE_LINUX_DEFAULT
):
Before (edited):
$ sudo turbostat -S --debug sleep 10
Avg_MHz %Busy Bzy_MHz TSC_MHz SMI CPU%c1 CPU%c3 CPU%c6 CPU%c7 CoreTmp PkgTmp Pkg%pc2 Pkg%pc3 Pkg%pc6 PkgWatt CorWatt GFXWatt
1 0.04 1654 3411 0 0.12 0.03 99.82 0.00 29 29 0.07 0.03 99.51 3.85 0.20 0.23
10.001629 sec
Make the change (using my method for configuration control):
~/config/etc/default$ cp /etc/default/grub ./
~/config/etc/default$ cp grub grub.original
~/config/etc/default$ nano grub
Change this:
GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1"
To this:
GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 intel_idle.max_cstate=1"
And update:
~/config/etc/default$ sudo cp grub /etc/default
~/config/etc/default$ sudo update-grub
~/config/etc/default$ sudo reboot -r now
Now check (edited):
$ sudo turbostat -S --debug sleep 10
Avg_MHz %Busy Bzy_MHz TSC_MHz SMI CPU%c1 CPU%c3 CPU%c6 CPU%c7 CoreTmp PkgTmp Pkg%pc2 Pkg%pc3 Pkg%pc6 PkgWatt CorWatt GFXWatt
0 0.02 1920 3411 0 99.98 0.00 0.00 0.00 39 39 0.00 0.00 0.00 10.49 6.66 0.23
10.001079 sec
Your should also see these messages in dmesg
and var/log/kern.log
(edited):
~$ dmesg | grep intel_idle
[ 1.019709] intel_idle: max_cstate 1 reached
$ grep intel_idle /var/log/kern.log
Mar 23 08:10:32 s15 kernel: [ 1.019709] intel_idle: max_cstate 1 reached
After having the same freeze-problems with linux and my asrock Q2900 I found on a German IT website the solution/workaround provided by Intel. (https://www.golem.de/news/intel-einfrieren-bei-intels-bay-trail-socs-durch-patch-abgefedert-1609-123546.html) There is a general problem with Bay-Trail-SoCs from Intel. The link to the patch: https://bugzilla.kernel.org/attachment.cgi?id=223851
Further information: This patch/script does obtain the power saving mode. The topic-solution above does remove this mode at all.