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Old   February 7, 2012, 17:01
Default Nodes per Core restriction?
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Max
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Is there a nodes per core restriction in CFX (educational)?
I have a 11mil cell mesh. If I run it on serial I get an error (something like to many integer values see below)
If I run it on more cores, it works.
I dont get that. Any ideas?

ERROR:

Quote:
ERROR #001100279 has occurred in subroutine ErrAction. |
| Message: |
| The total number of words needed for the Real stack exceeds the m- |
| aximum supported by the flow solver: 2,147,483,647. The solver w- |
| ill continue with the stack size clipped to that value.
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Old   February 7, 2012, 21:58
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Glenn Horrocks
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Wow, that is one big simulation - 2 billion for the real stack. Then clearly having a single simulation of this size is not possible, but if you split it up into some parallel runs it is.

I was not aware that this restriction existed.
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Old   February 8, 2012, 09:03
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Max
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I honestly don"t know whats blowing up the real stack.
Well, the cell count is high, its a duct with a wedge, hexa meshed for y+ around 1. I will be probably using it for running high volume concentration particle tracking, comparing it to experiments and DEM.
But thats just the first mesh validation for water with SST. 7Eq.

I was just wondering if that's a known issue. But since it runs parallel, it must be some limit on the single core runs.

Thanks
Max
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Old   February 8, 2012, 10:03
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There is a hard limit of that many words per stack per partition. It corresponds to about 16GB I think. Running in parallel reduces the memory required per partition, so you can drop below this limit.
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Old   June 8, 2013, 05:46
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Vishal
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No there is no restrictions for nodes per core in CFX (educational) as I know. The same problem I am also getting. The simulation will not show any error if it is run on parallel machines.
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Old   June 10, 2013, 22:26
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Stumpy's post answers the question - you need to run enough partitions to get all partitions below this stack limit. This stack limit will apply for the educational version of the software as well.
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