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[Bug 1188647] Re: Please change intel_pstate default to disable


I switched from Ubuntu 12.04.3 LTS with 3.80 kernel to Manjaro. The
reason is Ubuntu enables nvidia optimus technology via the latest 319
drivers. In practice Ubuntu is among the few distros where the current
implementation of works well. The frame rates with games go more than
twice than with Bumblebee and optirun command. All this is fine if your
intention are to use your laptop as a gaming machine. Sadly on my i7
ivybridge laptop, this also meant added heat to the tune of +10C and
more at idle as compared to Bumblebee as well as very low battery life,
I lost close to one and half hour.

I decided to try out Manjaro as it brings me to Arch minus the
headaches. Manjaro implements latest nvidia 325 drivers during install
with choice of kernel 3.4, 3.10 and latest 3.11 This also gave me a
chance to try out Intel's Pstate driver. In 3.11 it has matured greatly.
In practice compared to non Pstate kernel 3.4 the CPU at idle ran around
50C average whereas with 3.4 kernel they would run at 45C going down to
39c sometimes. This was kind of disappointing but I saw the cores
getting better utilized and system response snappier than cpu freq
ondemand. I then decided to install Intel Thermal Daemon and something
wonderful occurred. The idle temps didn't go down but peak temps under
full load never ever exceeded 60C with max of 68c under full load.
Without the daemon under full load they would touch up to 75, still
lower than close to 90c I was getting with Ubuntu and kernel 3.8

The temp average now puts Windows machine to shame, its lower under load
and also battery life with TLP is as good as Windows machine. So looks
like good things are in store for Linux in future. The kernel 3.11 is a
beauty, rock stable and very efficient with far lower memory
consumption. Time for Ubuntu to get into action on this.

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  Please change intel_pstate default to disable

Status in “linux” package in Ubuntu:
  Fix Released

Bug description:
  3.9 introduced a new default governor on SandyBridge CPUs called
  INTEL_PSTATE which, when built in and enabled (the default), removes
  all other governors (like our usual default, ondemand). 3.10 extended
  this to Ivybridge generation CPUs.

  In theory, this isn't an awful thing, as the new Intel pstate governor
  should be higher performance and give better power savings.  In

  In practice, it drives my CPUs to max frequency nearly constantly,
  spins my fans like mad and, somehow, does all of this while also
  eating enough CPU time in kernel threads to make my machine choppy,
  unresponsive, and unable to do simple things like play videos when I
  get off work.

  Therefore, I propose that we, for now, toggle intel_pstate to disable
  by default (I am using intel_pstate=disable on my command line right
  now, with great success), so it's still built in, and people can play
  with it, but it's off by default.

  ProblemType: Bug
  DistroRelease: Ubuntu 13.10
  Package: linux-image-3.9.0-4-generic 3.9.0-4.9
  ProcVersionSignature: Ubuntu 3.9.0-4.9-generic 3.9.4
  Uname: Linux 3.9.0-4-generic x86_64
  ApportVersion: 2.10.2-0ubuntu1
  Architecture: amd64
   /dev/snd/controlC0:  adconrad   2574 F.... pulseaudio
   [   30.633035] init: plymouth-stop pre-start process (2079) terminated with status 1
   [   36.086916] br0: port 1(eth0) entered forwarding state
  Date: Fri Jun  7 08:48:56 2013
  HibernationDevice: RESUME=UUID=73040efa-baec-458a-8307-3bca07b26c3c
  InstallationDate: Installed on 2012-12-09 (179 days ago)
  InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20121209)
  MachineType: LENOVO 4173LPB
  MarkForUpload: True
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.9.0-4-generic root=UUID=2222aad5-ef31-4428-973f-71740fc7cb6a ro intel_pstate=disable quiet splash vt.handoff=7
   linux-restricted-modules-3.9.0-4-generic N/A
   linux-backports-modules-3.9.0-4-generic  N/A
   linux-firmware                           1.109
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 09/13/2012
  dmi.bios.vendor: LENOVO
  dmi.bios.version: 8CET55WW (1.35 )
  dmi.board.asset.tag: Not Available
  dmi.board.name: 4173LPB
  dmi.board.vendor: LENOVO
  dmi.board.version: Not Available
  dmi.chassis.asset.tag: No Asset Information
  dmi.chassis.type: 10
  dmi.chassis.vendor: LENOVO
  dmi.chassis.version: Not Available
  dmi.modalias: dmi:bvnLENOVO:bvr8CET55WW(1.35):bd09/13/2012:svnLENOVO:pn4173LPB:pvrThinkPadT420s:rvnLENOVO:rn4173LPB:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
  dmi.product.name: 4173LPB
  dmi.product.version: ThinkPad T420s
  dmi.sys.vendor: LENOVO

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