Distributed parallel and memory usage

Jiricbeng · October 12, 2016, 04:58

Hi, the analysis I want to run takes more memory than available, it fails with the error 255, insufficient memory. I guess the analysis requires by 10-20% more memory than available. I was not able to make it run by other allocation factors or partitioning.
Therefore I installed the MPI platform on another computer and the distributed parallel calculation works - I tried it on a smaller testing analysis. But when I use it for the "big" analysis, it fails again with the same error - insufficient memory, error 255 etc.
It seems as if the analysis was first partitioned on the master computer and then it was sent to the slave computer.

ghorrocks · October 12, 2016, 06:34

Please post the section of the output file containing the error.

Jiricbeng · October 18, 2016, 07:03

I sorted it out by decreasing the number of cores on master computer. Because I decreased the core number for CFX on master computer, the master computer calculates smaller part of the analysis and it can get into the memory of the master computer (master computer used less memory). On the other hand, you have to have enough memory on the slave computers. Obviously, the memory distribution of the analysis among more computers is controlled by number of cores per each computer. I couldnt figure out how else to do it.

October 12, 2016, 04:58	Distributed parallel and memory usage	#1
Jiricbeng Senior Member Jiri Join Date: Mar 2014 Posts: 218 Rep Power: 13	Hi, the analysis I want to run takes more memory than available, it fails with the error 255, insufficient memory. I guess the analysis requires by 10-20% more memory than available. I was not able to make it run by other allocation factors or partitioning. Therefore I installed the MPI platform on another computer and the distributed parallel calculation works - I tried it on a smaller testing analysis. But when I use it for the "big" analysis, it fails again with the same error - insufficient memory, error 255 etc. It seems as if the analysis was first partitioned on the master computer and then it was sent to the slave computer.

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October 12, 2016, 06:34		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	Please post the section of the output file containing the error.

October 18, 2016, 07:03		#3
Jiricbeng Senior Member Jiri Join Date: Mar 2014 Posts: 218 Rep Power: 13	I sorted it out by decreasing the number of cores on master computer. Because I decreased the core number for CFX on master computer, the master computer calculates smaller part of the analysis and it can get into the memory of the master computer (master computer used less memory). On the other hand, you have to have enough memory on the slave computers. Obviously, the memory distribution of the analysis among more computers is controlled by number of cores per each computer. I couldnt figure out how else to do it.