kernel-packages team mailing list archive

[Henrique de Moraes Holschuh <1506050@xxxxxxxxxxxxxxxxxx>]

Chris Ng,

FWIW, there is a big chance that the issue you observed is ultimately
caused by thermald depending on weakly specified behavior that is known
to be processor-model-specific, and which we now know to be also
microcode-level specific.

Please refer to bug #1480349, and remove thermald from your system.
Don't run thermald on any Xeon boxes.

Removing thermald has a good chance of fixing the issue you observed, as
the modified Ubuntu version that detects and refuses to run on Xeon
boxes had not yet been sucessfully backported to vivid-lts at the time I
wrote this reply.

A reboot is required after removing thermald, to ensure all processor
MSRs are reset to firmware/kernel defaults.

If you do test the new microcode with thermald removed, please drop us a
note on this bug report.    Other users find this bug report through
Google, and the information would be helpful to them.   If removing
thermald does NOT fix your issue, I would really like to know about it
to further try to debug this issue.

-- 
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Packages, which is subscribed to linux-lts-vivid in Ubuntu.
https://bugs.launchpad.net/bugs/1506050

Title:
  intel cpu frequency is stuck at ~400mhz

Status in linux-lts-vivid package in Ubuntu:
  Invalid

Bug description:
  I upgraded an install of 14.0.4.3 to the LST Enablement Stack for
  Vivid (kernel 3.19) that is running on a Xeon E5-1630 V3 (a Haswell
  Quad-Core) .  Booting with 3.19 would result in the system being very
  sluggish.  'cpupower frequency-info' would report that the CPU was
  running at around 400mhz, as would 'cat
  /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq'.  The CPUs
  would remain around 400mhz regardless of load.

  This was using the intel_pstate driver and the powersave governor.
  Switching to the performance governor had no effect.  Using the acpi-
  cpufreq driver also had no effect, the system was still sluggish even
  though the reported frequencies in /sys/devices/.

  Eventually I tracked it down to the original install having had the
  intel_microcode package installed at some point.  Once I removed this
  then the CPU frequencies scaled correctly with load.  FYI the
  particular version installed was intel-microcode/trusty-updates,now
  2.20140624-t-1ubuntu2 amd64.

  ProblemType: Bug
  DistroRelease: Ubuntu 14.04
  Package: linux-image-3.19.0-30-generic 3.19.0-30.34~14.04.1
  ProcVersionSignature: Ubuntu 3.19.0-30.34~14.04.1-generic 3.19.8-ckt6
  Uname: Linux 3.19.0-30-generic x86_64
  NonfreeKernelModules: nvidia zfs zunicode zcommon znvpair zavl
  ApportVersion: 2.14.1-0ubuntu3.15
  Architecture: amd64
  Date: Wed Oct 14 12:38:05 2015
  InstallationDate: Installed on 2014-08-05 (434 days ago)
  InstallationMedia: Lubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2)
  SourcePackage: linux-lts-vivid
  UpgradeStatus: No upgrade log present (probably fresh install)

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