Metis decomposeParDict problem certain patches on one processor

diana · August 27, 2008, 06:14

Hi,

I have a case, where in parallel processing certain patches have to be on one processor. I can't use simple or hierarchical as decomposition methods because there I get error messages concerning cellfaces on different processors.

How can I define in metis that certain areas or certain patches have to be on one processor?

Or how do I define in metis cutting directions?

I would be glad for any help!!

Bye
Diana

gschaider · August 27, 2008, 06:41

Hi Diana!

The "easiest" way is to use the manual decomposition method.

You'll have to write a utility that assigns every cell to one processor and writes out a list to a file. The manual decompositon method needs that list as a parameter and will only generate the processor-meshes based on that information. All the balancing etc has to be done by your utility.

Bernhard

diana · August 27, 2008, 07:15

Hi Bernhard,

thanks for your tip!

I had the same idea, but I never found an information how the datafile has to look like.

Can you show me or say how to find information on this?

Bye
Diana

duongquaphim · September 9, 2009, 06:33

Hi Diana,

I am a new user of OpenFoam and I am also finding a way to construct a manual data file. Do you find a way to manage this problem?

Thanks

Duong

August 27, 2008, 06:14	Hi, I have a case, where in	#1
diana New Member Diana Gaulke Join Date: Mar 2009 Posts: 3 Rep Power: 17	Hi, I have a case, where in parallel processing certain patches have to be on one processor. I can't use simple or hierarchical as decomposition methods because there I get error messages concerning cellfaces on different processors. How can I define in metis that certain areas or certain patches have to be on one processor? Or how do I define in metis cutting directions? I would be glad for any help!! Bye Diana

August 27, 2008, 06:41	Hi Diana! The "easiest" way	#2
gschaider Assistant Moderator Bernhard Gschaider Join Date: Mar 2009 Posts: 4,225 Rep Power: 51	Hi Diana! The "easiest" way is to use the manual decomposition method. You'll have to write a utility that assigns every cell to one processor and writes out a list to a file. The manual decompositon method needs that list as a parameter and will only generate the processor-meshes based on that information. All the balancing etc has to be done by your utility. Bernhard __________________ Note: I don't use "Friend"-feature on this forum out of principle. Ah. And by the way: I'm not on Facebook either. So don't be offended if I don't accept your invitation/friend request

August 27, 2008, 07:15	Hi Bernhard, thanks for you	#3
diana New Member Diana Gaulke Join Date: Mar 2009 Posts: 3 Rep Power: 17	Hi Bernhard, thanks for your tip! I had the same idea, but I never found an information how the datafile has to look like. Can you show me or say how to find information on this? Bye Diana

September 9, 2009, 06:33		#4
duongquaphim Member Duong A. Hoang Join Date: Apr 2009 Location: Delft, Netherlands Posts: 93 Rep Power: 17	Hi Diana, I am a new user of OpenFoam and I am also finding a way to construct a manual data file. Do you find a way to manage this problem? Thanks Duong manuelffonseca likes this.

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