Ubuntu
compiz package

  1. Bug #101943
  2. Comment #70

Comment 70 for bug 101943

Revision history for this message
Noel J. Bergman (noeljb) wrote : Re: braid screensaver crashes system with compiz activated

> Do you have Unredirect Fullscreen Windows enabled? If so, does enabling Sync to VBlank help?

I did have the former enabled, not the latter. I've now tried with both off and both on. Not noticed a beneficial effect vis-a-vis this defect.

> These are in ccsm ...

Please note: Ubuntu does not include ccsm. Users must install either compizconfig-settings-manager or simple-ccsm. I installed the former, which is the one that I expect you meant.

NOW ... I do have some additional information. I walked through EVERY screensaver that comes with Hardy, using the preview window. Braid UNIQUELY and IMMEDIATELY caused both cores to be consumed. Most interestingly, even other high CPU usage screensavers, such as Helios, demonstrated the following characteristic:

  Cpu0 : 8.6%us, 1.0%sy, 76.4%ni, 13.0%id, 0.0%wa, 0.3%hi, 0.7%si, 0.0%st
  Cpu1 : 12.7%us, 2.7%sy, 21.3%ni, 62.7%id, 0.0%wa, 0.0%hi, 0.7%si, 0.0%st

NOTICE that the vast majority of CPU consumption is niced. BRAID uniquely had all of its CPU in the user column, consuming both cores:

  Cpu0 : 99.7%us, 0.0%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.3%si, 0.0%st
  Cpu1 : 84.2%us, 2.0%sy, 10.6%ni, 2.9%id, 0.0%wa, 0.0%hi, 0.3%si, 0.0%st

I could consistently recover the system by clicking on another screensaver, and waiting the several minutes it would take for the system to recognize the click. From what I can see, this CPU consumption is the immediate concern, and we can look into any memory issues after it is resolved.