Linux Power Management development
 help / color / mirror / Atom feed
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: "Hernandez Lopez, Fabiola" <fabiola.hernandez.lopez@intel.com>
Cc: "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Subject: Re: Frequency not returning to fixed value after AVX workload
Date: Mon, 14 Oct 2019 11:44:41 +0200	[thread overview]
Message-ID: <3340378.NBreQbsDsf@kreacher> (raw)
In-Reply-To: <67737C20FC7E4D44B44817ABFA5B1DCE6EC01C77@CRSMSX104.amr.corp.intel.com>

On Friday, October 11, 2019 7:45:55 PM CEST Hernandez Lopez, Fabiola wrote:
> Hi, 
> 
> We are seeing an unexpected behavior after applying AVX workloads. 
> After setting the CPU frequency to a fixed value with CPU Freq - userspace
> governor and applying heavy AVX workloads, the CPU frequency is decreased
> (as expected) but it never returns to the previously established value.

How do you measure the frequency?

> This does not happen on all cores, only on a single core. The only way to
> return to the desired frequency is by setting it through the command line
> again.

What exactly do you do to get the expected frequency back?

> We are wondering how can this change in frequency happen.

Is the target frequency in the turbo range?




  reply	other threads:[~2019-10-14  9:44 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-11 17:45 Frequency not returning to fixed value after AVX workload Hernandez Lopez, Fabiola
2019-10-14  9:44 ` Rafael J. Wysocki [this message]
2019-10-14 21:11   ` Hernandez Lopez, Fabiola
2019-10-14 21:23     ` Srinivas Pandruvada
2019-10-23 18:26       ` Hernandez Lopez, Fabiola

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=3340378.NBreQbsDsf@kreacher \
    --to=rjw@rjwysocki.net \
    --cc=fabiola.hernandez.lopez@intel.com \
    --cc=linux-pm@vger.kernel.org \
    --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