POEM@home News

[Nolion]

I got past the error messages thanks to suggestion from vaughan (download file from poem) combined with Dirk's app_info.xml (edited filename to match the downloaded file). Now just waiting to see if the project will send some tasks. This is the app_info.xml currently running...

<app_info>

   <app>

      <name>poemcl</name>

      <user_friendly_name>POEM++ OpenCL</user_friendly_name>

   </app>



   <file_info>

      <name>poemcl_0.2_x86_64-pc-linux-gnu__opencl_ati_100</name>

      <executable/>

   </file_info>

 

   <app_version>

      <app_name>poemcl</app_name>

      <version_num>1</version_num>

      <plan_class>opencl_ati_100</plan_class>

      <avg_ncpus>0.5</avg_ncpus>

      <max_ncpus>1.0</max_ncpus>

      <flops>2.1e10</flops>

      <coproc>

         <type>ATI</type>

         <count>0.5</count>

      </coproc>

      <cmdline></cmdline>

      <file_ref>

         <file_name>poemcl_0.2_x86_64-pc-linux-gnu__opencl_ati_100</file_name>

         <main_program/>

      </file_ref>

   </app_version>



</app_info>

[mmstick]

You'll find the performance to be rather terrible in Linux as compared to Windows, especially if you want to run any CPU tasks alongside the GPU one since for some reason any CPU task will starve the POEM OpenCL work units of CPU time, even if most of your processor is being spent idle. Example, a configuration I used in Windows got 90% GPU usage along with four World Community Grid tasks at the same time. In Ubuntu, I received 70% GPU usage with the same app info without CPU tasks, and 50% usage as soon as it started doing World Community Grid tasks, despite having 60% of my entire CPU being spent idle. I have no idea why this happens in Linux, maybe it will be fixed.

[Dirk Broer]

I observe more or less the exact same behaviour under Windows (at least under Win8 Dev-64).
When I run POEM I make sure the two instances each have a complete core/thread to themselves!
If it would run automatically, claiming that thread per WU all for itself -and not allowing just as many other projects as there are threads available-,
I would have made the 1 million already. As it is I am at 440k.
When left to itself POEM WUs will finish in 40 hours or so -but get heaps of credit-, when watched they run in 40 minutes.

[mmstick]

That is odd, you may want to try testing in Windows 7. Here is a picture of the kind of load I get on my system in Windows 7, and what you should be getting.

http://i635.photobucket.com/albums/u...k/b537e7ba.png

As you see, reported 90% load while running 4 WCG Wus, CPU load across all 8 cores is near maxed. Cant utilize it better than this. I wish I could get this level of utilization in Linux.

[Dirk Broer]

Looks better than on my A6-3500 or i3-2100 Win8 systems. As soon as there are three CPU projects running on the A6, or four on the i3, POEM freezes and estimated time to completion shoots up to 100+ hours I then close as much projects as needed in order to have a core free.
Sometimes I have to let POEM run all by itself to clear the queue. That 8-core of yours is a bulldozer, or a hyperthreaded i7?

[Nolion]

QUick update: after applying the changes to app_info.xml and downloading the application, I did get 3 WUs within a few hours. But the results, not so good. Two comp errors almost immediately and one download error (log says file size was slightly different from expected). Until I have more time to experiment I've reverted it back to the default environment without an app_info.xml so at least it will start crunching POEM work again. BTW I was looking into why my WU completion times increased after installing a second HD4850 in this system. I've already tried cutting the number of CPU tasks to as few as 5 on the 8 core CPU (i7-2600) but this didn't seem to help much.

[AMDave]

Have you O/C'd either the CPU or the GPU?

[mmstick]

I'm using a 4.4Ghz AMD FX-8120 yes. With one core I can only get 70% utilization, but an extra 3 cores gets 90%. It seems as if there is a scheduling issue with POEM in Windows 8 and Linux if you are getting that kind of behavior.

As for Nolion, did you manually download and install the 11.12 Catalyst driver? I had this issues because the default 11.11 catalyst driver installed by Ubuntu did not install OpenCL.

And here is the utilization in Ubuntu in comparison to Windows (just installed all the latest updates/kernel for it + 12.1 driver).
With CPU work units
http://i635.photobucket.com/albums/u...k/b98c350b.png
Without CPU work units
http://i635.photobucket.com/albums/u...k/a5909819.png

[Nolion]

CPU and GPUs are stock speed. It was a lot of work (for a Linux newbie) to get the dual GPU system functional so I definitely won't do anything that might make it unstable. Plus those 4850s run hot, not anxious to cook the hardware.

mmstick - Yes, I manually installed Catalyst 11.12 and also the APP SDK v2.6. POEM++ OpenCL v0.02 runs error-free when I let the project push the app out to my hosts and run without app_info.xml.

[mmstick]

That is odd, with my system running Ubuntu I can't even get it to grab units for GPU without the app_info.xml. Have you ever looked into the results of the work units that fail as to why POEM say they failed?