Thoughts on forcing 100% CPU usage in Ubuntu?

[musky]

My 4th I7 is not consistently loading all 8 recognized cores. It usually has 7 cores loaded close to 100% and the 8th runs close to 0%. The unused core changes fairly frequenly. As a result, my last several frames of my current bigadv have taken close to an hour each. The main difference between this one and the other 3 are 9.10 Desktop with the GUI running instead of 9.04 Server and this one connects with a wireless card instead of a wired connection.

I changed the nice level to -1 for all core processes and the executable, but I am still seeing the same thing. I am thinking this is yet another 9.10 process handling issue. I am going to try to shut down the GUI if I can figure out the wireless and see if that helps. Any other ideas? This one has me stumped.

 

[capreppy]

Interesting situation/question. I've never seen this, but I am using 8.04 in my Big Adv VM as I don't have greater than 8 cores yet.

 

[Mr. Pedantic]

Switch back to 8.04 server unless you desperately need the GUI, eg. if it's your primary rig. Otherwise, just scrap it.

 

[Kendrak]

You are going to want to go with 9.xx if you ever run more than 8 threads.

 

[musky]

This is my main rig, so I kinda need a GUI. Shutting down the GUI does seem to solve the problem, but I can't get the wireless connection to work without the GUI. I can't seem to set the essid on the wireless adapter from the command line.

 

[Mr. Pedantic]

Try another distro. Gentoo or Mandriva or something.

 

[keenan]

Set the processor affinity of each process so that they're all on separate CPUs. Install 'schedutils' package (might come with the distro) then

taskset -c <processor> -p <pid>

Processor id starts from 0, you can get the pid from ps or pgrep or the system monitor or whatever.

 

[musky]

Update:

Ubuntu 10.04 doesn't fold at all yet - some dynamic libc issue - looks really nice, though..
Ubuntu 9.04 - so far, so good - all cores at or around 100%, we will see how frame times look

Another fun evening with Ubuntu....

 

[APOLLO]

Ubuntu 10.04 doesn't fold at all yet - some dynamic libc issue - looks really nice, though..
Ubuntu 9.04 - so far, so good - all cores at or around 100%, we will see how frame times look.

Definitely let us know your thoughts on U9.04. I'm thinking of trying this as my next Linux distro experiment.

 

[musky]

31:20/frame - not bad for an I7 @ 3.64.

[03:55:14] Completed 0 out of 250000 steps  (0%)
[04:26:43] Completed 2500 out of 250000 steps  (1%)
[04:58:01] Completed 5000 out of 250000 steps  (2%)
[05:29:19] Completed 7500 out of 250000 steps  (3%)
[06:00:39] Completed 10000 out of 250000 steps  (4%)
[06:31:57] Completed 12500 out of 250000 steps  (5%)
[07:03:19] Completed 15000 out of 250000 steps  (6%)
[07:34:45] Completed 17500 out of 250000 steps  (7%)
[08:06:03] Completed 20000 out of 250000 steps  (8%)
[08:37:25] Completed 22500 out of 250000 steps  (9%)
[09:08:43] Completed 25000 out of 250000 steps  (10%)
[09:40:03] Completed 27500 out of 250000 steps  (11%)
[09:53:29] - Autosending finished units... [April 7 09:53:29 UTC]
[09:53:29] Trying to send all finished work units
[09:53:29] + No unsent completed units remaining.
[09:53:29] - Autosend completed
[10:11:27] Completed 30000 out of 250000 steps  (12%)
[10:42:45] Completed 32500 out of 250000 steps  (13%)
[11:14:07] Completed 35000 out of 250000 steps  (14%)
[11:45:26] Completed 37500 out of 250000 steps  (15%)

I'll crunch some numbers on these and add an update on recommendations for a starting point. I am thinking that 9.10 Server is the fastest (PPD/MHz) distro I am currently running, followed closely by 9.04 Desktop. 9.04 Server is lagging behind, but not terribly.