From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dirk Brandewie Subject: Re: Commit fcb6a15c2e7e (intel_pstate: Take core C0 time into account for core busy calculation) sucks rocks Date: Wed, 19 Feb 2014 16:03:40 -0800 Message-ID: <5305465C.7060806@gmail.com> References: <20140219224752.GA370@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140219224752.GA370@kroah.com> Sender: cpufreq-owner@vger.kernel.org To: Greg KH Cc: dirk.brandewie@gmail.com, "Rafael J. Wysocki" , cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org On 02/19/2014 02:47 PM, Greg KH wrote: > Hi Dirk, > > I've been having some huge slowdowns on my box building kernels, and I > took the time to bisect it down to commit > fcb6a15c2e7e76d493e6f91ea889ab40e1c643a4 (intel_pstate: Take core C0 > time into account for core busy calculation). With that patch reverted > on Linus's current tree, my build speeds are back up to the normal rate. > > The difference is huge, 2 minutes to do a kernel build with that patch > reverted, 8-10 minutes with it applied! With all of the stable kernel > builds and other trees, this is a huge problem for my workload (all I do > is kernel builds it seems...) > > I see some patches you marked as "fixes" that you sent to Rafael, do you > want me to test any of those? How am I the only one seeing this > problem, do you need my cpu information or anything else? Can you give me a description of you build system? CPU, number of sockets, building from/to local media. Any special setup I should use here for my test? If you have time having the output of turbostat for a build with and without would be very useful. On my single socket Sandybridge test system I don't see any difference. I tested against v3.10.30, v3.12.11 and v3.13.3 > > Oh, and because of the problems, I'll just drop this patch from the > -stable trees for now, I don't want to pollute them with the issue until > it is resolved properly. > > thanks, > > greg k-h > -- > To unsubscribe from this list: send the line "unsubscribe cpufreq" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >