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Active Member
HomaPumpen
Posts: 6
Registered: ‎07-15-2013

Performance in Task Manager only 40%

181 Views, 4 Replies
07-15-2013 02:36 AM

Hello,

 

we have installed CFD on a Dell workstation with 16 cores and 64GB RAM. I am looking at the Task Manager during simluation and I can see that CFD is using all 16 cores but the overall performance is about 40% only. even the fan speed of the workstation is not going up.

 

What can I do to make the machine use all of the capacities?

 

Thanks,

Martin

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Active Member
HomaPumpen
Posts: 6
Registered: ‎07-15-2013

Re: Performance in Task Manager only 40%

07-15-2013 04:39 AM in reply to: HomaPumpen

One additional infromation: It is a 8 core CPU and it is showing 16 cores due to hyper threading.

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Employee
scott.werner
Posts: 16
Registered: ‎11-18-2011

Re: Performance in Task Manager only 40%

07-16-2013 02:40 PM in reply to: HomaPumpen

Martin,

 

For each SimCFDSolver.exe process, we set the Priority to Low. We do this so your system is usable during solving. You can increase the priority on each SimCFDSolver.exe process by: Task Manager > Right Click on Process Name > Set Priority. Warning: You can crank up the priority of a non-system process so high that it can cause the system to become unstable and non-responsive because the system processes don't get enough time (http://stackoverflow.com/questions/8658469/does-changing-the-process-priority-in-windows-task-manage...

Scott Werner
SQA Engineer
Digital Simulation
Autodesk, Inc.
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Active Member
HomaPumpen
Posts: 6
Registered: ‎07-15-2013

Re: Performance in Task Manager only 40%

07-17-2013 01:45 AM in reply to: HomaPumpen

Thanks for the quik response.

 

One more question: Do I hve to switch of the hyper threading?  Is there a diference in stability and calculation speed with and without hyper threading?

 

Martin

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Product Support
apolo.vanderberg
Posts: 307
Registered: ‎08-31-2011

Re: Performance in Task Manager only 40%

07-17-2013 06:18 AM in reply to: HomaPumpen

Martin,

The main reason you see that value in the Task Manager is that we are only running 1 solver / physical core.

8cores means 8solvers. Each solver will use ~100% of the core its assigned to. So as far as windows will report due to hyperthreading taht <100% is utilized as it shows all 16cores, and only 8 of which are being taxed fully. So for your machine if we were running at full speed we would read 50% utilization via taskmanager.

There are some instances where disabling HT can improve performance of the solver. With HT turned off you would then see this percentage go up to 80/90%

 

Apolo

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