Re: [tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2014-04-14 Thread Davidlohr Bueso
On Tue, 2014-04-08 at 21:43 +, Brown, Len wrote: > Davidlohr, > > Thanks for the note. > > Ideally (on Linux in general, and on servers, in particular) we strive > for the performance impact of power saving features to be small enough > to be considered in "measurement noise". > > Your repor

Re: [tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2014-04-09 Thread Peter Zijlstra
On Tue, Apr 08, 2014 at 09:43:54PM +, Brown, Len wrote: > #1: skip flush for C1 > #2: skip flush for C1 and C1E One stray thought I had: IFF the erratum is due to the cache flushing of the higher C states, these two patches should still be correct while also (possibly) avoiding the performance

RE: [tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2014-04-08 Thread Brown, Len
Davidlohr, Thanks for the note. Ideally (on Linux in general, and on servers, in particular) we strive for the performance impact of power saving features to be small enough to be considered in "measurement noise". Your report for 160 core Westmere AIM numbers being hit at 10-25% shows 15% measu

Re: [tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2014-03-18 Thread Peter Zijlstra
On Tue, Mar 18, 2014 at 07:14:04PM -0700, Jason Low wrote: > On Tue, Mar 18, 2014 at 2:16 AM, Peter Zijlstra wrote: > > On Mon, Mar 17, 2014 at 05:20:10PM -0700, Davidlohr Bueso wrote: > >> On Thu, 2013-12-19 at 11:51 -0800, tip-bot for Len Brown wrote: > >> > Commit-ID: 40e2d7f9b5dae048789c64672

Re: [tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2014-03-18 Thread Jason Low
On Tue, Mar 18, 2014 at 2:16 AM, Peter Zijlstra wrote: > On Mon, Mar 17, 2014 at 05:20:10PM -0700, Davidlohr Bueso wrote: >> On Thu, 2013-12-19 at 11:51 -0800, tip-bot for Len Brown wrote: >> > Commit-ID: 40e2d7f9b5dae048789c64672bf3027fbb663ffa >> > Gitweb: >> > http://git.kernel.org/tip/40

Re: [tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2014-03-18 Thread Peter Zijlstra
On Mon, Mar 17, 2014 at 05:20:10PM -0700, Davidlohr Bueso wrote: > On Thu, 2013-12-19 at 11:51 -0800, tip-bot for Len Brown wrote: > > Commit-ID: 40e2d7f9b5dae048789c64672bf3027fbb663ffa > > Gitweb: > > http://git.kernel.org/tip/40e2d7f9b5dae048789c64672bf3027fbb663ffa > > Author: Len Bro

Re: [tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2014-03-17 Thread Davidlohr Bueso
On Thu, 2013-12-19 at 11:51 -0800, tip-bot for Len Brown wrote: > Commit-ID: 40e2d7f9b5dae048789c64672bf3027fbb663ffa > Gitweb: http://git.kernel.org/tip/40e2d7f9b5dae048789c64672bf3027fbb663ffa > Author: Len Brown > AuthorDate: Wed, 18 Dec 2013 16:44:57 -0500 > Committer: H. Peter Anvin

[tip:x86/urgent] x86 idle: Repair large-server 50-watt idle-power regression

2013-12-19 Thread tip-bot for Len Brown
Commit-ID: 40e2d7f9b5dae048789c64672bf3027fbb663ffa Gitweb: http://git.kernel.org/tip/40e2d7f9b5dae048789c64672bf3027fbb663ffa Author: Len Brown AuthorDate: Wed, 18 Dec 2013 16:44:57 -0500 Committer: H. Peter Anvin CommitDate: Thu, 19 Dec 2013 11:47:39 -0800 x86 idle: Repair large-serv