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@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
-- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
