Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Oct 05, 2016 at 10:47:53AM +0530, Viresh Kumar wrote: > Sorry for being late Andreas :( > > On 14-09-16, 16:56, Andreas Herrmann wrote: > > First of all, thanks for your hardwork in getting these numbers out. > Really appreciate it. > > > Below is some trace data. I hope it is of some

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Oct 05, 2016 at 10:47:53AM +0530, Viresh Kumar wrote: > Sorry for being late Andreas :( > > On 14-09-16, 16:56, Andreas Herrmann wrote: > > First of all, thanks for your hardwork in getting these numbers out. > Really appreciate it. > > > Below is some trace data. I hope it is of some

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On 22-09-16, 19:54, Andreas Herrmann wrote: > On Mon, Sep 19, 2016 at 10:39:18PM +0300, Stratos Karafotis wrote: > > Just an idea. I would split the frequency range (max_freq - min_freq) > > into ~10 steps. But I'm not familiar with the affected systems and > > of course I can't prove this is an

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On 22-09-16, 19:54, Andreas Herrmann wrote: > On Mon, Sep 19, 2016 at 10:39:18PM +0300, Stratos Karafotis wrote: > > Just an idea. I would split the frequency range (max_freq - min_freq) > > into ~10 steps. But I'm not familiar with the affected systems and > > of course I can't prove this is an

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

Sorry for being late Andreas :( On 14-09-16, 16:56, Andreas Herrmann wrote: First of all, thanks for your hardwork in getting these numbers out. Really appreciate it. > Below is some trace data. I hope it is of some help. > > (A) - sampling 10s period when system is idle > (B) - sampling 10s

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

Sorry for being late Andreas :( On 14-09-16, 16:56, Andreas Herrmann wrote: First of all, thanks for your hardwork in getting these numbers out. Really appreciate it. > Below is some trace data. I hope it is of some help. > > (A) - sampling 10s period when system is idle > (B) - sampling 10s

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Mon, Sep 19, 2016 at 10:39:18PM +0300, Stratos Karafotis wrote: > On Mon, Sep 19, 2016 at 7:16 PM, Andreas Herrmann wrote: > > On Fri, Sep 16, 2016 at 09:58:42PM +0300, Stratos Karafotis wrote: > >> Hi, > >> > >> [ I 'm resending this message, because I think some

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Mon, Sep 19, 2016 at 10:39:18PM +0300, Stratos Karafotis wrote: > On Mon, Sep 19, 2016 at 7:16 PM, Andreas Herrmann wrote: > > On Fri, Sep 16, 2016 at 09:58:42PM +0300, Stratos Karafotis wrote: > >> Hi, > >> > >> [ I 'm resending this message, because I think some recipients didn't > >>

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Mon, Sep 19, 2016 at 7:16 PM, Andreas Herrmann wrote: > On Fri, Sep 16, 2016 at 09:58:42PM +0300, Stratos Karafotis wrote: >> Hi, >> >> [ I 'm resending this message, because I think some recipients didn't receive >> it. ] >> >> On 16/09/2016 12:47 μμ, Andreas Herrmann

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Mon, Sep 19, 2016 at 7:16 PM, Andreas Herrmann wrote: > On Fri, Sep 16, 2016 at 09:58:42PM +0300, Stratos Karafotis wrote: >> Hi, >> >> [ I 'm resending this message, because I think some recipients didn't receive >> it. ] >> >> On 16/09/2016 12:47 μμ, Andreas Herrmann wrote: >> > On Wed, Sep

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Fri, Sep 16, 2016 at 09:58:42PM +0300, Stratos Karafotis wrote: > Hi, > > [ I 'm resending this message, because I think some recipients didn't receive > it. ] > > On 16/09/2016 12:47 μμ, Andreas Herrmann wrote: > > On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > >> On

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Fri, Sep 16, 2016 at 09:58:42PM +0300, Stratos Karafotis wrote: > Hi, > > [ I 'm resending this message, because I think some recipients didn't receive > it. ] > > On 16/09/2016 12:47 μμ, Andreas Herrmann wrote: > > On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > >> On

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

Hi, On 16/09/2016 12:47 μμ, Andreas Herrmann wrote: > On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: >> On 01-09-16, 15:21, Andreas Herrmann wrote: >>> On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > I am _really_ worried about such hacks in drivers to negate

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

Hi, On 16/09/2016 12:47 μμ, Andreas Herrmann wrote: > On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: >> On 01-09-16, 15:21, Andreas Herrmann wrote: >>> On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > I am _really_ worried about such hacks in drivers to negate

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > On 01-09-16, 15:21, Andreas Herrmann wrote: > > On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > > > I am _really_ worried about such hacks in drivers to negate the effect of > > > a > > > patch, that was actually

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > On 01-09-16, 15:21, Andreas Herrmann wrote: > > On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > > > I am _really_ worried about such hacks in drivers to negate the effect of > > > a > > > patch, that was actually

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > On 01-09-16, 15:21, Andreas Herrmann wrote: ---8<--- > > I started with the value return as "nominal latency" for PCC. This > > was 30 ns on the test system and made things worse. I've tested > > other values as well unitl

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > On 01-09-16, 15:21, Andreas Herrmann wrote: ---8<--- > > I started with the value return as "nominal latency" for PCC. This > > was 30 ns on the test system and made things worse. I've tested > > other values as well unitl

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > On 01-09-16, 15:21, Andreas Herrmann wrote: > > On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > > > > I am _really_ worried about such hacks in drivers to negate the effect of > > > a > > > patch, that was actually

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Wed, Sep 07, 2016 at 10:32:01AM +0530, Viresh Kumar wrote: > On 01-09-16, 15:21, Andreas Herrmann wrote: > > On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > > > > I am _really_ worried about such hacks in drivers to negate the effect of > > > a > > > patch, that was actually

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On 01-09-16, 15:21, Andreas Herrmann wrote: > On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > > I am _really_ worried about such hacks in drivers to negate the effect of a > > patch, that was actually good. > > > Did you try to increase the sampling period of ondemand governor to

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On 01-09-16, 15:21, Andreas Herrmann wrote: > On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > > I am _really_ worried about such hacks in drivers to negate the effect of a > > patch, that was actually good. > > > Did you try to increase the sampling period of ondemand governor to

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > On 19-08-16, 14:21, Andreas Herrmann wrote: > > > > Commit 6393d6a102 (cpufreq: ondemand: Eliminate the deadband effect) > > introduced a performance regression for systems using pcc-cpufreq and > > ondemand governor. This is

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On Mon, Aug 29, 2016 at 11:31:53AM +0530, Viresh Kumar wrote: > On 19-08-16, 14:21, Andreas Herrmann wrote: > > > > Commit 6393d6a102 (cpufreq: ondemand: Eliminate the deadband effect) > > introduced a performance regression for systems using pcc-cpufreq and > > ondemand governor. This is

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On 19-08-16, 14:21, Andreas Herrmann wrote: > > Commit 6393d6a102 (cpufreq: ondemand: Eliminate the deadband effect) > introduced a performance regression for systems using pcc-cpufreq and > ondemand governor. This is measurable with different workloads. E.g. > wall-clock time for kernel

Re: [PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

On 19-08-16, 14:21, Andreas Herrmann wrote: > > Commit 6393d6a102 (cpufreq: ondemand: Eliminate the deadband effect) > introduced a performance regression for systems using pcc-cpufreq and > ondemand governor. This is measurable with different workloads. E.g. > wall-clock time for kernel

[PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

Commit 6393d6a102 (cpufreq: ondemand: Eliminate the deadband effect) introduced a performance regression for systems using pcc-cpufreq and ondemand governor. This is measurable with different workloads. E.g. wall-clock time for kernel compilation significantly increased. The elimination of the

[PATCH 1/1] cpufreq: pcc-cpufreq: Re-introduce deadband effect to reduce number of frequency changes

Commit 6393d6a102 (cpufreq: ondemand: Eliminate the deadband effect) introduced a performance regression for systems using pcc-cpufreq and ondemand governor. This is measurable with different workloads. E.g. wall-clock time for kernel compilation significantly increased. The elimination of the