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Bug Power Red Hat Software Linux

Linux Kernel Power Bug Is Fixed 145

An anonymous reader writes "The Linux kernel power bug that caused high power usage for many Intel Linux systems has finally been addressed. Matthew Garrett of Red Hat has devised a solution for the ASPM Linux power problem by mimicking Microsoft Windows' power behavior in the Linux kernel. A patch is on LKML for this solution to finally restore the battery life under Linux."
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Linux Kernel Power Bug Is Fixed

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  • Re:overblown (Score:4, Interesting)

    by QuantumRiff ( 120817 ) on Friday November 11, 2011 @06:50PM (#38030326)

    yes.. My 8 hours of battery life in windows and 5 hours in Linux running PowerTop to disable as much as possible is just sensationalism..

  • by UnoriginalBoringNick ( 1562311 ) on Friday November 11, 2011 @09:50PM (#38031770)

    Something like this perhaps? []

    From: Bill Gates
    Sent: Sunday, January 24, 1999 8:41 AM
    To: Jeff Westorinon; Ben Fathi
    Cc: Carl Stork; Nathan Myhrvold; Eric Rudder
    Subject: ACPI extensions

    One thing I find myself wondering about is whether we shouldn't try and make the "ACPI" extensions somehow Windows specific.

    It seems unfortunate if we do this work and get our partners to do the work and the result is that Linux works great without having to do the work.

    Maybe there is no way to avoid this problem but it does bother me.

    Maybe we could define the APIs so that they work well with NT and not the others even if they are open.

    Or maybe we could patent something related to this.

  • Re:overblown (Score:5, Interesting)

    by inglorion_on_the_net ( 1965514 ) on Friday November 11, 2011 @11:29PM (#38032330) Homepage

    Yes. It sickes me that Slashdot has followed Phoronix's lead in calling this a Linux bug. It isn't. The bug is in hardware not reporting that it is ASPM (Active State Power Management) capable.

    As I understand it, the history of this thing is like:
      1. Linux implements ASPM
      2. This causes some hardware to fail, because it isn't ASPM capable
      3. Linux is fixed to detect if the hardware reports ASPM capability, and doesn't use ASPM if the hardware says it doesn't support that
      4. Michael Larabel of Phoronix notices that Linux power consumption has risen on some hardware, calls it a bug in Linux
      5. Folks investigate, figure out that some hardware reports no ASPM capability, even though it is ASPM capable, and implement a kernel parameter to force Linux to use ASPM, even if the hardware says it doesn't support it
      6. Michael Larabel keeps talking about the Linux power regression writes post after post about how it still hasn't been fixed
      7. Someone figures out how Windows detects ASPM support on hardware that doesn't report it, and implements the same heuristic in Linux
      8. Now, Slashdot claims the Linux bug has been fixed, even though it wasn't a bug in Linux, and Linux has had a workaround for almost as long as we've known about the issue

    Seriously, guys. Bad reporting. This is _not_ what I come to Slashdot for. There are hundreds of sites that will give me half truths, common misconceptions, and the occasional nugget of truth. Strive to be better than those.

  • Re:Good News (Score:5, Interesting)

    by hairyfeet ( 841228 ) <bassbeast1968 AT gmail DOT com> on Saturday November 12, 2011 @04:23AM (#38033364) Journal

    Well I read it as 'MSFT realizes the standards don't mean shit to ODMs and worked around it" while the Linux guys try to stick to the standards and it bit them in the ass. Building and repairing PCs 6 days a week frankly this does NOT surprise me because if you've looked at the BIOS some of these ODMs put out frankly shoddy shit is the ONLY word to describe it!

    I had to tell a customer just last week he was either gonna have to have me order an EXACTLY identical stick for his desktop or simply do without a stick because the POS BIOS on the eMachines would not allow you to run dual sticks unless they were a perfect match! all because some ODM decided that having a simple switch in BIOS for single or dual mode was just too much bother. I've also run into OEMs that put dual core HSFs on quads, fans so shitty I'm surprised they run at all, PSUs that are so close to the absolute max limit on the machine that literally a single fan or DVD burner would have overloaded the thing, it seems like if it can save them 2c and it'll pass POST that is all they give a shit about.

    I'm all for having low prices but when the design decisions actually shorten the life of the machine and risk all kinds of errors and hassles for the user that's where i draw the line. Some of the low end Dells and eMachines are so badly built frankly i'm amazed they make it to the end of warranty, talk about junk!

"What the scientists have in their briefcases is terrifying." -- Nikita Khrushchev