[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#365441: xserver-xorg-video-savage: XVideo extension using too much CPU

On Sun, Apr 30, 2006 at 11:40:37AM +0200, Michel Dänzer wrote:
>On Sat, 2006-04-29 at 23:11 -0400, John Gruenenfelder wrote:
>> Package: xserver-xorg-video-savage
>> Version: 1:
>> Severity: normal
>> After upgrading to the new modular X packages, I find that my X setup
>> now uses an excessive amount of CPU time to play back video when using
>> the XVideo extension.
>> The machine is my MythTV box.  It is a small Shuttle box with builtin
>> "S3 Inc. VT8375 [ProSavage8 KM266/KL266]" video on the motherboard.
>> With the previous X packages video playback was excellent.  The problem
>> appears to affect any program which makes use of the XVideo extension
>> (MythTV, mplayer, xine, etc.).
>This is most likely a duplicate of
>http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=362755 .

Sorry for dropping this... I hadn't had any time to fiddle with my Myth box
for too long.

My problem is, it seems, only tangentially related to that issue.  It is true
that the MTRR is not set properly, but even after I set it manually the X
server is still using far too much CPU.

Without MTRR set:  > 100% CPU needed for software decoding and X server and
                   video skips a lot.
With MTRR set:     ~40% CPU used just by X server while video plays.

That's still far too much.  The machine in question has an Athlon XP 2000
CPU.  On another slightly faster computer (unfortunately, not the same
graphics chipset), while playing the same video file the X server will consume
just under 5% of the CPU.

So now, between CPU decoding costs and the CPU used by this Xv inefficiency,
playing a simple video will take 70-80% of the CPU.  This means skipping can
(and does) occur from time to time if the computer is tasked with something
else in the background.

This was not an issue with X 6.9, but it is a problem with 7.0 and newer
(still running Debian/Sid).

--John Gruenenfelder    Research Assistant, UMass Amherst student
                        Systems Manager, MKS Imaging Technology, LLC.
Try Weasel Reader for PalmOS  --  http://gutenpalm.sf.net
"This is the most fun I've had without being drenched in the blood
of my enemies!"
        --Sam of Sam & Max

Reply to: