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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
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 index

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-11 17:45 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

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