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From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Tue, 14 Jun 2022 15:25:54 +0200
Message-ID: <CAJZ5v0gYNeson93Zs-ZR7PVQEfwK3GBFpHuBGCk3DeDeeJH6LQ@mail.gmail.com>
Subject: Re: [PATCH 15/20] ACPICA: executer/exsystem: Warn about sleeps
 greater than 10 ms
To:     Paul Menzel <pmenzel@molgen.mpg.de>
Cc:     "Rafael J. Wysocki" <rafael@kernel.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Bob Moore <robert.moore@intel.com>,
        Linux ACPI <linux-acpi@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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Hi Paul,

Sorry for the delay.

On Sun, May 22, 2022 at 1:28 AM Paul Menzel <pmenzel@molgen.mpg.de> wrote:
>
> Dear Rafael,
>
>
> Am 21.05.22 um 18:11 schrieb Rafael J. Wysocki:
> > On Mon, Apr 11, 2022 at 9:04 PM Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> >>
> >> From: Paul Menzel <pmenzel@molgen.mpg.de>
> >>
> >> ACPICA commit 2a0d1d475e7ea1c815bee1e0692d81db9a7c909c
> >>
> >> Quick boottime is important, so warn about sleeps greater than 10 ms.
> >>
> >> Distribution Linux kernels reach initrd in 350 ms, so excessive delays
> >> should be called out. 10 ms is chosen randomly, but three of such delays
> >> would already make up ten percent of the boottime.
> >>
> >> Link: https://github.com/acpica/acpica/commit/2a0d1d47
> >> Signed-off-by: Bob Moore <robert.moore@intel.com>
> >> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > I have decided to revert this, because it spams logs with unuseful
> > warnings on many production systems.
>
> Thank you for the information. Can you please give an example?

Personally, I saw this on Dell XPS13 9360 and 9380 machines in my
office, but it has been reported to be that it was visible on multiple
systems in the Linux client power lab at Intel.

You can also see here that Linux is not the only affected OS:
https://github.com/acpica/acpica/pull/780

Thanks!