From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 58001] "ondemand" CPU governor never raises frequency (Dell XPS 12) Date: Sun, 23 Mar 2014 22:39:18 +0000 Message-ID: References: Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: cpufreq-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: cpufreq@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=58001 Paul Johnson changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |pauljohn@ku.edu --- Comment #14 from Paul Johnson --- I see problem too. May not be kernel, but in Ubuntu in particular. I think the up_threshold is set at 95, too high, and keeping it lower is a bit of a hassle. My system now: $ uname -a Linux dellap7 3.11.0-13-generic #20-Ubuntu SMP Wed Oct 23 07:38:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux CPU never goes fast in ondemand unless I do this: su -c "echo -n 70 > /sys/devices/system/cpu/cpufreq/ondemand/up_threshold" I find 70 is low enough to solve the sluggishness problem in Ubuntu. I wanted to make that permanent. Its not easy in newer Ununtu. I find that suggestions to edit /etc/sysfs.conf are unhelpful. I found one post that claims that the Ubuntu stack does not create /sys/devices/system/cpu/cpufreq/ondemand soon enough, so the sysfs adjustments have no effect. The best explanation I've found is #5 in this thread https://bugs.launchpad.net/ubuntu/+source/sysfsutils/+bug/955918. A suggestion is to insert this in /etc/rc.local, so it will run, or wait until the rest of the system has done what it is supposed to. I've not got advice from an expert on whether this is bad or good, but I'm doing it, following that example. until [ -d "/sys/devices/system/cpu/cpufreq/ondemand" ]; do sleep 1 done echo -n "70" > /sys/devices/system/cpu/cpufreq/ondemand/up_threshold Another thing users with same up_threshold problem might benefit from use of a applet that can turn CPUs to performance mode instantly. It works in user space, no admin required (that was a new thing to me, anyway). Look for this: indicator-cpufreq That's handy when you can't seem to get the CPUs to go fast. Performance mode makes a laptop hotter (in several senses :) ). >From a user's point of view, this has all become very confusing. What is controlling speed now? There's no cpufreqd anymore? Some guidance from kernel experts would be pleasant. There were posts claiming that Intel discouraged ondemand, maybe that factors into problem (Intel Dev says "Stop using OnDemand!!!" https://bbs.archlinux.org/viewtopic.php?id=163524&p=2). I suppose that must have been bogus, since we are still using ondemand a year later. But not cpufreqd, so far as I can tell, in a fresh Ubuntu install. -- You are receiving this mail because: You are the assignee for the bug.