From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: g.medini@eurosoft.it
Cc: linux-rt-users@vger.kernel.org
Subject: Re: High latency of a system based on 5.19 rt
Date: Mon, 2 Oct 2023 12:02:57 +0200 [thread overview]
Message-ID: <20231002100257.FQFcIFo9@linutronix.de> (raw)
In-Reply-To: <S1JV78$805284328FE38E68AC9E7D23F35846D8@eurosoft.it>
On 2023-09-25 18:30:44 [+0200], g.medini@eurosoft.it wrote:
>
> Hi All, I'm struggling with a realtime issue I have.
Hi,
> Using trace I've found a problem related to CONFIG_X86_DEBUG_FPU that was introducing very large latency.
Do you have a trace and numeric value of "very large latency" for
CONFIG_X86_DEBUG_FPU?
> Removing this I have another one where the solution is not so trivial.
>
> The problem I've actually seems related to i915 driver.
>
> With a particular load for the graphic card (basically using ALT-TAB to switch from graphical windows or pressing the Win like button to resize all the graphical windows to the screen) I see an huge latency that gives problem to an rt task I need for my application.
>
> I've tried everything to optimize the sytem.
>
> As expected I find little enhancement that help me to mitigate the problem (core isolation and so on) but the basic problem remain the same (it happens with X11 and Wayland also).
What is the latency problem? The wake up trace shows a wake up from
gnome to irq-work. Is the graphic/ i915 lagging or something else?
> Hoping someone can help me.
>
> Gianluca
>
> Cordiali saluti
> Best regards
Sebastian
next prev parent reply other threads:[~2023-10-02 10:03 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-25 16:30 High latency of a system based on 5.19 rt g.medini
2023-09-25 17:02 ` Ralf Mardorf
2023-09-26 7:04 ` Mike Galbraith
2023-09-26 12:34 ` Clark Williams
[not found] ` <CAMLffL8=zW0Bv47R=r3=Lh9==OjDrM=FTJZgmm6PYGOyTedeBA@mail.gmail.com>
2023-09-26 13:15 ` Mike Galbraith
2023-10-02 10:05 ` Sebastian Andrzej Siewior
2023-10-02 11:58 ` Mike Galbraith
2023-10-02 14:16 ` Sebastian Andrzej Siewior
2023-10-02 15:20 ` Mike Galbraith
2023-10-02 10:02 ` Sebastian Andrzej Siewior [this message]
-- strict thread matches above, loose matches on Subject: below --
2023-10-03 13:47 g.medini
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