[Duduke]

Are you viewing your items in library mode?

Do you have 'Tripple Buffering' option in your xorg.conf?

[slight]

This is just idling on the home screen not browsing anything.

Yes I have Triple Buffering enabled after seeing it recommended elsewhere in the forum. I'll try without.

[slight]

No difference with triple buffering off.

[tslayer]

Very possibly this: http://ubuntuforums.org/showthread.php?t=546868

It also has a link to a bugid.

Even with vsync on, I still get one core used on idle.

[averylinden]

I'm not seeing this with latest svn on Gutsy 32bit with standard proprietary nvidia driver. The only modifications I've made to xorg.conf is to turn on TripleBuffer.

Core2 6300 @ 1.86GHz
GeForce 7300 GS

[slight]

Ah well spotted. But yeah vsync doesn't seem to have any effect for me either.

[slight]

I've done some more testing and this behaviour is definitely specific to XBMC not general to GL apps. More specifically, it only happens when XBMC is fullscreen (1280x720 'Desktop'). This is while idling on the home screen, or idling on any of the other screens I've tried.

I've installed Google Earth, and Planet Penguin Racer (tuxracer) and neither of thm put the CPU to 100%. Tuxracer maxes out around 50% CPU while playing the game (fullscreen) and Google Earth hit's 100% for a few seconds while it loads then settles down to single figures while idling and scrolling in small increments, I've tried it windowed and full screen.

Here's a zip of sysprof rerposrts while each app was running, including xbmc in fullscreen and xbmc in windowed as separate profiles.

http://slight.overtops.org/tmp/more_sysprof.zip

[slight]

Developers? Seems to be an XBMC issue. I'm happy to try to provide more info if you need it.

[d4rk]

I've been quite busy for the past few days. I did take a look at the profile. It's possible that somehow some GL function is taking a software path in the XBMC render, although I can't imagine what that would be on a 8600GT, given that many lower end NVidia cards don't seem to exhibit this behavior (including my 7600GS).

[slight]

Thanks for the response. Not hassling for a fix, just wanted to make sure you were aware that this *appears* to be XBMC specific even if not actualy an XBMC bug.

I might see if I can get a cachegrind profile of it and see if that gives any clues.

[nurgle]

I too have an 8600GT card and get 100% CPU usage while in the GUI. When playing video's this drops to less than 5% usage.

[topfs2]

I too have an 8600GT card and get 100% CPU usage while in the GUI. When playing video's this drops to less than 5% usage.

Sounds like vsync issue.

I have 8800gts and 5600fx, never 100% nor the issue slight is having :S

But slight which programs have you tried that are more advanced and uses shaders?
Warsow, Nexquiz, Saurbraten or ET:QW?
The 3 first are free and should be available in repo and might prove if it's driver related? Still games tend too use up all cpu

Thx

[tslayer]

Topfs2, I thought it was vsync too, but I'm pretty sure I have it enabled as well. I also have an 8600GT.

FYI, it uses one core at 100%. Not both.

[nurgle]

I have vsync enabled in both nvidia driver applet and within XBMC itself and still 1 core is 100% with XBMC process.

[slight]

I've tried with and without vsync enabled in both XBMC and xorg.conf so I don't think it's that.

I'll try Warsow when I get a chance.

In the mean time I've run valgrind's callgrind tool on it and it's come up with a potentially contradictory result, it's saying that ~50 of the total call time is being taken up with a call in libasound_module_rate_speexrate.so.

I wonder if the 'emulated CPU' valgrind uses is running that library, but obviously not the nvidia kernel module, meaning that's being slowed down but the nvidia module isn't. Which is a bit of a pain in the arse, can't see a way of getting around that

As I understand it that lib is something to do with dmix resampling, I don't have any dmix stuff in my asound.conf or ~/.asoundrc, in fact I don't have anything in either of those files.