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Linux Kernel Suffering Power Management Regression?
An anonymous reader writes "It appears that there's a big power management regression in the Linux kernel for the 2.6.38 and 2.6.39 development releases, including the kernel to ship with Ubuntu 11.04 next week. It's reportedly causing a 10~30% increase in power consumption on many laptop computers."
I think this is something that only Power Users will notice. It's not something important for the common user.
I don't know--this seems really common with the last dozen kernel releases or so. Power regressions, file system regressions, graphics speed regressions, blah blah blah. With every new kernel release Phoronix reports some serious regressions in various subsystems.
This is presumably not an intentional regression though, more likely just some new/updated code that is causing the CPU to be more busy when the machine is effectively idle than it was previously. It isn't like someone said "hey, Linus, do you mind if I make the kernel eat more power?"!
Ever notice it is only Phoronix reporting that?
When did steam come to linux again?
Sorry, but I want to see this backed up another source before I just go believing it.
Well, what Linus is focused on is breaking user code - if it worked in a released kernel, you will not break it in any future kernel. I don't think there's any strict rule that performance must always be better or power consumption lower. Particularly if you're not doing something "right" and have to add additional checks/locks/synchronization for corner cases that can slow you down, they generally value correctness over performance. That's the case in many of Phoronix' sensationalist news, a development release is very fast but when you make it work 'right' the performance is no longer that impressive. That stuff will happen as close to the bleeding edge as most of the things they report on are. Of course, they do find real regressions too but it's easy to get the wrong impression...
Live today, because you never know what tomorrow brings
Would be handy if the suite (or the user) would actually produce graphs with different enough colors to make sense which line is which...
I'm on .38 on multiple computers and I'm not seeing these issues, perhaps it's a configuration error on their end (assuming they compile the kernel themsleves for testing) or a configuration error on whatever distribution they test with?
Ever notice it is only Phoronix reporting that?
Do you know of any other organization with a large automated regression testing system for linux kernels? That's not just me being snarky, its a serious question - who else beside phoronix is doing this sort of wide-scale testing on a constant basis?
When information is power, privacy is freedom.
Ever notice it is only Phoronix reporting that?
When did steam come to linux again?
Wine 0.9.6x, as I recall...
Well, that would explain a great deal why my Dell laptop has been overheating and shutting off without warning since that last kernel build. It's shut off three times today and I haven't even done any intensive computing.
Methinks I need a new box.
One would expect that there is some sort of automated performance regression suite that is run regularly (say, daily) to catch offending commits.
Power consumption raised significantly in natty
this is the actual confirmed (4-13) bug report on the Launchpad at least a particular instance.
Personally I do not run the extra baggage of Ubuntu on my mobile linux device. (netbook)
When did they start putting unconfirmed or untested bug reports on Slashdot? Sure TFA says much to warrant further investigation... but not to have people like me get curious. (Just my opinion)
We should start a new Slashdot and return control to the geeks. It actually wouldn't be that hard to get some users to
Why would anyone want to run linux on a laptop? Well, I run linux on my laptop. At first I had it set up to dual boot, but after months of not using the Windows partition I canned it and have never missed it. During the period I had both operating systems set up, I could compare them. Windows (Vista as installed at the factory) was dog slow and buggy (and before you poke fun at Vista, XP was just as bad on other laptops as received). Linux was snappy, remarkably stable, and supported the hardware very well with the exception of the oddball fingerprint reader which was a crappy idea anyway. It is a Lenovo X301 with SSD. If you stay away from Dell crap, 95% of laptops are pretty routine for linux. Even a lot of Dells are fine, but too many of them have oddball crap that is problematic.
I have successfully installed and run various linux distros on a Compaq/HP X1000, an HP2133 mini, a Samsung X460, and the Lenovo, as well as maybe a couple of dozen desktops, including pretty-much-black-box Shuttles and Aopen minis, as well as oddball home-builts, over the last 10 years or so. Things have gotten a lot better over the last several years in terms of video and wireless support. Hardware support is so good currently that it is far better than Windows, where you have to track down drivers for every piece of hardware on your own.
Having said that, my nephew has no trouble at all wiping the OEM Windows off of his laptops, one after the other, and installing his own fresh retail copies of Windows. He claims it performs much better without the bundled crap. I don't have the patience for that myself, and can't divine why anyone would WANT to run Windows, anyway.
I do think you miss the point when you claim that it is a waste of "resources" for linux to go to a lot of work to support a myriad of hardware. The resources you speak of are open source software engineers who are basically in it for the love of the challenge. Most of them are not interested in working on boring apps, anyway, and the non-hardware-related kernel proper has plenty of manpower working on it. The part of the kernel that is not hardware related doesn't even need a lot of manpower. Those are guys with vary special knowledge. The development resources available to linux are basically unlimited. Yes, the software engineers paid by corporations to work on linux make important contributions, including hardware support, but a lot of guys, particularly in hardware support, are independent geniuses on their own time. A lot of pieces of hardware owe their linux support to these individuals donating their time as a sideline because they relish the work, and individually are interested enough in some particular piece of hardware for their own use to figure it out.
Yes, it's probably due to that one thing you heard about.
<xml><I><am><so><damn>Web 2.0</damn></so></am></I></xml>
Phoronix is shit. Pure, grade-A shit. Worthless.
They have _nothing_ of value to add to anything. Sensationalist crap which is not reported elsewhere, _because it it not an issue_.
Regressions in the development kernels are part of the process. Even actively trying to avoid Phoronix, I have seen tons of those non-news about some random regression and the breathless follow-up that, lo surprise, they didn't just release but fix the issue. Woooooo!
Phoronix is shit and it should be blacklisted globally on Slashdot and anywhere else. Stop linking to them, stop commenting on them (other than making others aware of this).
Rant over.
run lm-profiler (part of laptop mode tools if I recall correctly) and see what demands that your hard drive be awoken from sleep :)
I lost the ability to hibernate my machines in the last few kernels, how about fixing that?
~corporate tool, but employed~