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Posts: 5
Registered: ‎11-03-2012
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16 Core Machine only using 8 Cores

371 Views, 8 Replies
11-03-2012 08:36 AM

I have a dual 8 core workstation that I send jobs with the remote solving feature in CFD.  When I tell it to use all 16 cores it only seems to load the workstation to about 50% or half the cores.  What might I need to change so that it will use all 16 cores.

 

Thanks

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Royce_adsk
Posts: 507
Registered: ‎08-24-2011

Re: 16 Core Machine only using 8 Cores

11-05-2012 05:39 AM in reply to: sveenman

Are you sure it is really 16 pysical cores? Many people get confused when hyperthreading is turned on and task manager says there are 16 cores when really there are only 8 physical cores.

 

What are your CPU Hardware Specs?

 

-Royce



Royce Abel
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Posts: 5
Registered: ‎11-03-2012

Re: 16 Core Machine only using 8 Cores

11-05-2012 06:16 AM in reply to: Royce_adsk

I talked with our IT guys and they said it was not using hyper threading.  According to properties under my computer it is a Xeon E5-2680 @ 2.7GHz and the task manger shows 16 cores.

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Royce_adsk
Posts: 507
Registered: ‎08-24-2011

Re: 16 Core Machine only using 8 Cores

11-05-2012 06:26 AM in reply to: sveenman

If you open your resource monitor and review your CPU tab, how many CPUs are listed and how many of them indicated the 'Parked' state?

 

Thanks,

Royce



Royce Abel
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Re: 16 Core Machine only using 8 Cores

11-05-2012 06:37 AM in reply to: Royce_adsk

8 of them are listed as parked.  So what does that mean?

 

-Steve

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Royce_adsk
Posts: 507
Registered: ‎08-24-2011

Re: 16 Core Machine only using 8 Cores

11-05-2012 07:00 AM in reply to: sveenman

This means that you have 8 physical cores with 8 virtual cores created with hyperthreading.

 

-Royce



Royce Abel
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Posts: 5
Registered: ‎11-03-2012

Re: 16 Core Machine only using 8 Cores

11-05-2012 07:06 AM in reply to: Royce_adsk

Thanks for the help I will let the IT Group know.

 

-Steve

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Member
Posts: 5
Registered: ‎11-03-2012

Re: 16 Core Machine only using 8 Cores

11-15-2012 05:18 AM in reply to: sveenman

I have now added a 2nd 8 core cpu to this machine.  When I run a simulation now it uses ~25% of the processors.  So becasue hyperthreading is on that means it is still only using 8 of the 16 actual cores.  What am I missing now?

 

Thanks

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akarlsso
Posts: 7
Registered: ‎08-30-2011

Re: 16 Core Machine only using 8 Cores

11-27-2012 05:42 AM in reply to: sveenman

I remember from an earlier release that in a standard license the solver could use up to 4 virtual cores.

I dont remember which release this came in but it was the greatest enhancement I've seen so far.

 

If this is still the case its likely to be an explanation to why you dont see a performance increase

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