GPU tasks cause MT tasks to sit idle

Message boards : Questions and problems : GPU tasks cause MT tasks to sit idle
Message board moderation

To post messages, you must log in.

AuthorMessage
zombie67
Avatar

Send message
Joined: 14 Feb 06
Posts: 139
United States
Message 44901 - Posted: 15 Jul 2012, 2:35:48 UTC

http://yafu.dyndns.org/yafu/forum_thread.php?id=106

Has this been brought up before? Is there a solution (other than running the MT tasks in a VM)?
Reno, NV
Team: SETI.USA
ID: 44901 · Report as offensive
zombie67
Avatar

Send message
Joined: 14 Feb 06
Posts: 139
United States
Message 44955 - Posted: 19 Jul 2012, 19:00:02 UTC

Nothing?
Reno, NV
Team: SETI.USA
ID: 44955 · Report as offensive
Profile Jord
Volunteer tester
Help desk expert
Avatar

Send message
Joined: 29 Aug 05
Posts: 15480
Netherlands
Message 44957 - Posted: 19 Jul 2012, 20:26:31 UTC - in response to Message 44955.  

As far as I know, it's normal. With any MT application, it'll wait until all CPU cores are available. As long as part of any core is in use with another application, the MT app won't start.

The solution might be to set 'On multiprocessors, use one core less than your maximum, so it can cater for the GPU AND run in the MT app. Not sure if that would work, but you can try.

Of course, if you feel that the working is wrong, post to the alpha or development email list. That's the quickest way to the developers.
ID: 44957 · Report as offensive
Richard Haselgrove
Volunteer tester
Help desk expert

Send message
Joined: 5 Oct 06
Posts: 5080
United Kingdom
Message 44958 - Posted: 19 Jul 2012, 20:39:10 UTC - in response to Message 44957.  

As far as I know, it's normal. With any MT application, it'll wait until all CPU cores are available. As long as part of any core is in use with another application, the MT app won't start.

The solution might be to set 'On multiprocessors, use one core less than your maximum, so it can cater for the GPU AND run in the MT app. Not sure if that would work, but you can try.

Of course, if you feel that the working is wrong, post to the alpha or development email list. That's the quickest way to the developers.

Not quite. I was running AQUA's MT tasks OK with a GPU task alongside - though of course many BONCs have come and gone since AQUA folded, so that isn't current news.

I think the clue is in the linked thread - running two GPU tasks at 0.7 CPUs each, so the total CPU reservation is more than one whole CPU - I think that's the point where the MT get blocked.

Running one GPU task at a time would be worth a test: if that works, wrapping the GPU app in an app_info that only claims 0.49 <ncpus> might allow two to run - that doesn't change the way the apps run in any way, just fools the scheduler.
ID: 44958 · Report as offensive

Message boards : Questions and problems : GPU tasks cause MT tasks to sit idle

Copyright © 2024 University of California.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.