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From: Greg Gallagher <greg@embeddedgreg.com>
To: Robert Berger <xenomai.list@gmail.com>
Cc: Pierre FICHEUX <pierre.ficheux@smile.fr>, xenomai <xenomai@xenomai.org>
Subject: Re: Arm64 jitter
Date: Mon, 5 Apr 2021 01:24:19 -0400	[thread overview]
Message-ID: <CALLqZ8SVi6GasNB3x9ofJ-DbAK56yjjw6uj1j1FSfoc2Wa4fAw@mail.gmail.com> (raw)
In-Reply-To: <66c7ed10-b868-bf1c-7960-1d5094655546@gmail.com>

On Sun, Apr 4, 2021 at 4:49 PM Robert Berger <xenomai.list@gmail.com> wrote:

> Hi,
>
> My comments are in-line:
>
> On 02/04/2021 07:54, Greg Gallagher via Xenomai wrote:
> >>
> >>
> > Looks like this is affecting 4.19/5.4 arm and arm64.  Still
> investigating,
> > hopefully I'll have a root cause shortly.
>
> With cyclictest, stress-ng and a loadavg of over 12 I see a jitter of
> approx. 55 usec on an arm32: i.mx6 quad.
>
> Did not yet start testing on arm64.
>
> >
> > -Greg
> >
>
> Regards,
>
> Robert
>
Hi,

I think I've tracked down a couple issues that could be causing this.  I'll
hopefully have an update this week with a fix.

Thanks for testing,

Greg

      reply	other threads:[~2021-04-05  5:24 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-29  9:20 Arm64 jitter Pierre FICHEUX
2021-03-29  9:21 ` Pierre FICHEUX
2021-03-29 11:43   ` Greg Gallagher
2021-03-29 12:06     ` Pierre FICHEUX
2021-03-29 13:17       ` Greg Gallagher
2021-03-29 13:35         ` Pierre FICHEUX
2021-04-02  4:54           ` Greg Gallagher
2021-04-04 20:49             ` Robert Berger
2021-04-05  5:24               ` Greg Gallagher [this message]

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