Choppy video in all apps... [SOLVED]

mointrigue · Last edited by mointrigue on Thu Aug 17, 2006 9:45 pm; edited 1 time in total

I'm noticing a system wide problem on my box with video. Initially all of my video will play fine whether it is saved to the hard disk or via DVD (after a/v problem was fixed), but after a certain amount of time, which varies, all video will become extremely choppy, with stutters and starts. It becomes unwatchable. It affects xine, mplayer, vlc, flash, you name it, regardless of video type.

I tried different output drivers, and they don't seem to make a difference. I can't see anything significant happening in CPU or memory use during playback, with the exception of tiny jumps when it is recovering from a stutter, but those are only jumps up to 1.5% CPU use. Since it was universal, I began to suspect some kind of problem in KDE or X so I've tried restarting the X server, but that doesn't actually fix the problem.

Just for kicks I tried stopping X, unloading and then reloading the nvidia module, and restarting X. Still choppy. The only thing that seems to restore the video is a full reboot. Very strange.

I'm running x86 Gentoo on an Athlon64 X2 4400+ CPU with a GeForce 6800XT (PCI-E). I'm using modular X 7.0, and latest ~x86 nvidia drivers. Any help would be very much appreciated!

belrpr · Guru Joined: 22 May 2006 Posts: 440

Check if your dma is running for your hard disk and dvd drive!

mointrigue · Posted: Thu Aug 03, 2006 1:47 pm Post subject:

Enverex · Posted: Thu Aug 03, 2006 2:23 pm Post subject:

If it's SATA it will be on. To tweak SCSI and SATA use sdparm.

mointrigue · Posted: Thu Aug 03, 2006 2:34 pm Post subject:

mointrigue · Posted: Thu Aug 03, 2006 8:29 pm Post subject:

I've noticed that during xine-check that MTRR is supported but disabled on my system. The script says it only really helps AGP cards.

Should this be an area of concern for me even though I use an AMD CPU with a PCI-E graphics card? If so, how do I enable MTRR? I'm kind of grasping at straws at this point.

mointrigue · Posted: Thu Aug 03, 2006 11:54 pm Post subject:

Ha ha, I'm an idiot. I forgot to include the mtrr argument on the kernel line of my grub.conf.

I did some stress tests running by playing a bunch of video files at once, but so far it's been fine. I think my X is more responsive too.

The problem was rather unpredictable before, so I'll wait 24 hours and if there aren't any more issues I'll mark this one solved.

mointrigue · Posted: Fri Aug 04, 2006 11:53 pm Post subject:

Hmm, the MTRR setting helped, but when I got home today video was extremely choppy again, causing CPU spikes. Also, when trying to navigate file system with Konquerer I ran into trouble where the little expanding box animation that accompanies opening a folder would slow to a crawl. As before, a reboot was the only way to fix the situation. Also video choppiness displayed itself in xine, mplayer, vlc, etc. The filebrowsing responsiveness was also an issue.

I'm not sure where the problem is coming from xorg's interaction with my video card or an issue with the hard-drive. My hard drives are both SATA, with the root sitting on a Raptor at 10000RPM and the addtional storage on a 7200RPM 3.0GB/s SATA. So I don't think that the hardware is lacking in speed.

I'm really lost as to where to look next, and help would be really great!

NeddySeagoon · Posted: Sat Aug 05, 2006 12:00 am Post subject:

mointrigue,

If a reboot fies it for a while, it sounds like a memory leak.

Reboot, run top and play some videos, more and more memory being used is ok,
more and more swap being used is not. That indicates a program is requesting memory but not releasing it again, hen the term 'leak'
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

mointrigue · Posted: Sat Aug 05, 2006 4:25 am Post subject:

Hmm, the choppiness seems to start before top indicates that I've used any of my swap. I tried watching individual programs swap column in top but they seem to be consistently the same amount. Although I have noticed on this system that I get a lot of duplicate processes for some programs (e.g. kmail, firefox, xine, vlc, amarok). However, when I close the program all the processes disappear, so they don't seem to be hanging. Could that be part of the problem?

I've been curious if that is part of it. Since this is a fresh install on my first dual core system I'm not sure what to be expecting when I check out process lists.

Thanks.

NeddySeagoon · Posted: Sat Aug 05, 2006 12:02 pm Post subject:

mointrigue,

what you are seeing there are the individual threads of the same program. They all use the same resources, so if firefox is running 10 threads and it reports 10Mb of memory used in each thread, it the same 10Mb of memory, not 100Mb total.
Its not your problem.

Is it an issue reading from CD/DVD or from your hard drive ?

Are you using DMS on the drive ?
hdparm /dev/hd... will show you. DMA is part of the SATA standard - it cannot be turned off.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

mointrigue · Posted: Sat Aug 05, 2006 5:22 pm Post subject:

NeddySeagoon,

DMA is enabled for both DVD drives, and the choppiness when it occurs will happen with both DVDs and local hard drive files. In fact, along with the aforementioned Konqueror issue, also mouseover popup displays in firefox and really all apps, although it is most notable in firefox.

Although there is one weird thing. There is a particular error message I get when playing DVDs. It doesn't appear during local file playback, but it might be related.

NeddySeagoon · Posted: Sat Aug 05, 2006 9:47 pm Post subject:

mointrigue,

Linux will use all of memory one way or another - unused memory is just wasted, so memory use alone is not a bad sign but swapping is.

Lets start from the beginning. Post your lspci ouput and the output from mplayer (in the xterm) when you don't ask it to play anything.
I'm not convinced that DMA is on for your DVD drives.
How are your DVDs and HDDs connected ?
IDE, SATA, SCSI ... ?
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

mointrigue · Posted: Sat Aug 05, 2006 11:12 pm Post subject:

NeddySeagoon,

My DVD drives are both IDE connections. Both are masters on on two IDE connections because I was having difficulty enabling DMA on the slave drive, so I just connected it to my motherboard's secondary IDE connector. My hard drives are both SATA.

NeddySeagoon · Posted: Sun Aug 06, 2006 10:36 am Post subject:

mointrigue,

All that looks good.

The next step is to play a DVD with mplayer (from an xterm) and run top too.
When the choppyness sets in post the content of the mplayer window and the top window.
Do not stop either to make the 'snapshots'
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

mointrigue · Posted: Tue Aug 08, 2006 12:13 am Post subject:

Grr, now that I'm trying to capture data, the issue is taking its sweet time showing up again. I'm getting heavy dropped frames in some programs but nowhere near the magnitude of what was happening before and mplayer isn't really showing the issue yet, but it's getting closer to that point. I'm certain I haven't changed anything since the problem last showed up, so I'm just going to keep playing video until I can get it to reappear.

mointrigue · Posted: Wed Aug 09, 2006 12:46 am Post subject:

This still isn't nearly as bad as it normally gets (typically the video stops and starts and barely plays at all once the problem manifests), it's still being stubborn, but I'm getting dropped frame warnings in xine, and it really shows there. Occasionally I can get something to play smoothly, but mplayer doesn't seem to be giving me warnings, but it starts dropping frames heavily if I so much as open a file browsing window. I have no idea why this problem hasn't fully manifested itself yet. In the past it usually surfaces in about 24 hours of the system booting (assuming I've been watching videos). However, I am getting dropped frames and chop in mplayer now, although it will recover for a bit before it starts dropping again, which I suppose is to be desired, although I even so much as open a filebrowser it will slow down noticably. Regardless, the hardware on this machine should smoke my old system, and I never had these kind of issues on that box. So I'm going to post that output now, with more to follow if I can finally duplicate the full effect of this problem.

NeddySeagoon · Posted: Wed Aug 09, 2006 10:31 am Post subject:

mointrigue,

That all looks fairly normal. The CPU is lightly loaded and has been for some time, althogh the laod has increased in the last 15 min. Swap contains 48k of of stuff used only at startup/shutdown, so thats normal too.

Check dmesg for any signs that you have DMA timeouts associated with your DVD player. That would indicate that the kernel has reverted to PIO mode, which would also account for your CPU load increase.
In PIO mode, the maximum data rate is much lower and more CPU time is required, since the CPU needs to read every byte individually from the drive. (ok, it can read words, since the IDE link is 16 bit wide).
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

mointrigue · Posted: Wed Aug 09, 2006 2:14 pm Post subject:

Hmm, there isn't anything in dmesg, but in /var/log/messages I found some stuff.

There's actually a ton of these, but I'm only including the last three times the message appears. The final line is dated at about a half hour after my last reboot.

NeddySeagoon · Posted: Wed Aug 09, 2006 4:37 pm Post subject:

mointrigue,

You should only see that once on startup - not 'tons'.
You are really looking for

mointrigue · Posted: Wed Aug 09, 2006 4:54 pm Post subject:

Hmm, I'm not seeing any timeout errors. It looks like DMA is being enable correctly, but I could be missing something.

NeddySeagoon · Posted: Wed Aug 09, 2006 6:36 pm Post subject:

mointrigue,

That all looks good - as you say, no timeout errors.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

djbeenie · Apprentice Joined: 09 Nov 2005 Posts: 207

I had to put this in the tail end of my grub to get my cd/dvd rom to work without choppyness.

hdc=noprobe

Not sure it will help in your case.
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Linux Newbie

mointrigue · Posted: Thu Aug 10, 2006 1:39 pm Post subject:

Okay, the problem has manifested in force now, video stutters and stops alot and the aforementioned konqueror slowdown is also occuring. I grabbed some output from playing a hard disk file. Swap has been at 320k for about 24 hours. The problem manifested when I first sat down at the computer this morning. I don't know if this will help identify it or not.

NeddySeagoon · Posted: Thu Aug 10, 2006 3:24 pm Post subject:

mointrigue,

CPU load