Bug 39321 - [sna kde] swrast on common paths?
Summary: [sna kde] swrast on common paths?
Alias: None
Product: xorg
Classification: Unclassified
Component: Driver/intel (show other bugs)
Version: 7.6 (2010.12)
Hardware: Other Linux (All)
: medium major
Assignee: Chris Wilson
QA Contact: Xorg Project Team
Keywords: NEEDINFO
Depends on:
Reported: 2011-07-18 01:44 UTC by Alexander
Modified: 2011-10-03 09:52 UTC (History)
2 users (show)

See Also:
i915 platform:
i915 features:


Description Alexander 2011-07-18 01:44:51 UTC
I've noticed that Xorg with intel DDX with enabled SNA consumes 20-40% CPU or even more, I've seen 80%. This happens on window switch or on konsole tab switch with 3D effects and without.

"perf top" shows that most resources used by: __kmalloc, page_fault and __memcpy_ssse3. Where __memcpy_ssse3 is on top.

I've built DDX from git. I'm using vanila kernel from git 3.0.0-rc7+ and Debian linux with installed xorg and mesa following versions:
ii  xserver-xorg                        1:7.6+7server
ii  xserver-xorg-core                   2:
ii  libgl1-mesa-dri                     7.11~0-2
ii  libgl1-mesa-glx                     7.11~0-2
ii  libglu1-mesa                        7.11~0-2

Please let me know if I can help more with investigating this issue.
Comment 1 Chris Wilson 2011-07-18 02:27:16 UTC
I need the callgraph to see which paths are hitting sw. In all likelihood it is probably just due to KDE being silly and not using RENDER.
Comment 2 Eugeni Dodonov 2011-09-02 06:14:04 UTC
@Alexander, could you generate a callgraph using callgrind for example?

E.g., like explained at http://docs.kde.org/stable/en/kdesdk/kcachegrind/using-kcachegrind.html and http://valgrind.org/docs/manual/cl-manual.html..

It is hard to say what happens, kmalloc, page_fault and memcpy are probably always the top ones, but to see why the performance is grim we need to know who calls them via what code paths :).

Comment 3 Eugeni Dodonov 2011-10-03 08:10:16 UTC
Comment 4 Alexander 2011-10-03 08:23:08 UTC

Sorry for delay, now seems it works OK.

Best regards,

On 10/03/2011 06:10 PM, bugzilla-daemon@freedesktop.org wrote:
> https://bugs.freedesktop.org/show_bug.cgi?id=39321
> Eugeni Dodonov<eugeni@dodonov.net>  changed:
>             What    |Removed                     |Added
> ----------------------------------------------------------------------------
>             Keywords|                            |NEEDINFO
> --- Comment #3 from Eugeni Dodonov<eugeni@dodonov.net>  2011-10-03 08:10:16 PDT ---
> Ping?
Comment 5 Eugeni Dodonov 2011-10-03 09:52:48 UTC
Closing then, thanks!

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