linux-pm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Doug Smythies" <dsmythies@telus.net>
To: "'Rafael J. Wysocki'" <rjw@rjwysocki.net>
Cc: "'LKML'" <linux-kernel@vger.kernel.org>,
	"'Len Brown'" <len.brown@intel.com>,
	"'Srinivas Pandruvada'" <srinivas.pandruvada@linux.intel.com>,
	"'Peter Zijlstra'" <peterz@infradead.org>,
	"'Giovanni Gherdovich'" <ggherdovich@suse.cz>,
	"'Francisco Jerez'" <francisco.jerez.plata@intel.com>,
	"'Linux PM'" <linux-pm@vger.kernel.org>
Subject: RE: [RFC/RFT][PATCH] cpufreq: intel_pstate: Work in passive mode with HWP enabled
Date: Mon, 24 Aug 2020 07:54:54 -0700	[thread overview]
Message-ID: <000f01d67a26$891b9340$9b52b9c0$@net> (raw)
In-Reply-To: <3169564.ZRsPWhXyMD@kreacher>

On 2020.05.21 10:16 Rafael J. Wysocki wrote:

...
> 
> The INTEL_CPUFREQ_TRANSITION_DELAY_HWP value has been guessed and it very well
> may turn out to be either too high or too low for the general use, which is one
> reason why getting as much testing coverage as possible is key here.
> 
> If you can play with different INTEL_CPUFREQ_TRANSITION_DELAY_HWP values,
> please do so and let me know the conclusions.
...

Hi Rafael,

Since my v7 reply the other day about results for 347 Hz work/sleep frequency
periodic workflows [1], I have been testing at 73 Hertz work/sleep frequency.
And am now testing this:

-#define INTEL_CPUFREQ_TRANSITION_DELAY_HWP     5000
+#define INTEL_CPUFREQ_TRANSITION_DELAY_HWP     10000

Which shows promise for the schedutil governor, which no
longer drives prematurely into the turbo range, consuming
excessive amounts of energy as compared to passive without
HWP.

The ondemand governor is still very bad. The only way I
have found to get it behave is to force max=min=target_pstate,
in addition to the above.

It will be quite some time before I have well organized feedback.
In the meantime if anyone has suggestions for an optimal
INTEL_CPUFREQ_TRANSITION_DELAY_HWP value, I would be grateful.
Otherwise I'll attempt to find it via tests.

... Doug

[1] https://marc.info/?l=linux-pm&m=159769839401767&w=2



      parent reply	other threads:[~2020-08-24 14:58 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-21 17:15 [RFC/RFT][PATCH] cpufreq: intel_pstate: Work in passive mode with HWP enabled Rafael J. Wysocki
2020-05-25  1:36 ` Francisco Jerez
2020-05-25 13:23   ` Rafael J. Wysocki
2020-05-25 20:57     ` Francisco Jerez
2020-05-26  8:19       ` Rafael J. Wysocki
2020-05-26 15:51         ` Doug Smythies
2020-05-26 17:42           ` Rafael J. Wysocki
2020-05-26 18:29         ` Francisco Jerez
2020-05-25 15:30 ` Doug Smythies
2020-05-25 21:09   ` Doug Smythies
2020-06-15  6:18 ` Doug Smythies
2020-08-24 14:54 ` Doug Smythies [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='000f01d67a26$891b9340$9b52b9c0$@net' \
    --to=dsmythies@telus.net \
    --cc=francisco.jerez.plata@intel.com \
    --cc=ggherdovich@suse.cz \
    --cc=len.brown@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=rjw@rjwysocki.net \
    --cc=srinivas.pandruvada@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).