system / solver capacity

jai · July 29, 2009, 00:41

how do i calculate maximum or optimum amount of elements can be solve in a machine(based on number of node, ram..)?

and

stumpy · July 29, 2009, 06:51

While there are some rules of thumb, the memory required will depend on the particular case and the models used. If you run a case with x number of nodes, then just look in the out file before the first iteration to see how much memory was used. Memory will scale linearly with the number of nodes - so 2x nodes requires twice the memory etc.

jai · July 29, 2009, 13:46

if my problem having x number of elements and I'm solving by serial type (ie: 1 processor) so it utilize some y amount of memory.
this same x number of elements solving by 2 processors means it utilize 2*y memory.

Is this correct?
mean time I'll check it

I've 4 processors and 4 node license and 8GB ram.
how many number of element i could run optimally?
how to calculate to know this?

if my problem size is 10 million elements and how do i know minimum configuration require for this?

ghorrocks · July 29, 2009, 19:11

Hi,

The size analysis you require should be determined by a sensitivity analysis. After you have determined the mesh size and timestep size you require you then look at what computer is required to run it.

Why don't you run a 1M and a 2M node simulation and look at the memory use? Then you can extrapolate it out to the size you require.

Glenn Horrocks

jai · July 30, 2009, 13:04

please could you explain in details with one example

shogologo · July 31, 2009, 02:51

Check "CPU and Memory Requirements" section under ANSYS CFX-Solver Manager User's Guide.

July 29, 2009, 00:41	system / solver capacity	#1
jai Member jaikrishna Join Date: Mar 2009 Location: chennai Posts: 56 Rep Power: 17	how do i calculate maximum or optimum amount of elements can be solve in a machine(based on number of node, ram..)? and

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July 29, 2009, 06:51		#2
stumpy Senior Member Join Date: Apr 2009 Posts: 531 Rep Power: 21	While there are some rules of thumb, the memory required will depend on the particular case and the models used. If you run a case with x number of nodes, then just look in the out file before the first iteration to see how much memory was used. Memory will scale linearly with the number of nodes - so 2x nodes requires twice the memory etc.

July 29, 2009, 13:46		#3
jai Member jaikrishna Join Date: Mar 2009 Location: chennai Posts: 56 Rep Power: 17	if my problem having x number of elements and I'm solving by serial type (ie: 1 processor) so it utilize some y amount of memory. this same x number of elements solving by 2 processors means it utilize 2*y memory. Is this correct? mean time I'll check it I've 4 processors and 4 node license and 8GB ram. how many number of element i could run optimally? how to calculate to know this? if my problem size is 10 million elements and how do i know minimum configuration require for this?

July 29, 2009, 19:11		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,696 Rep Power: 143	Hi, The size analysis you require should be determined by a sensitivity analysis. After you have determined the mesh size and timestep size you require you then look at what computer is required to run it. Why don't you run a 1M and a 2M node simulation and look at the memory use? Then you can extrapolate it out to the size you require. Glenn Horrocks

July 30, 2009, 13:04		#5
jai Member jaikrishna Join Date: Mar 2009 Location: chennai Posts: 56 Rep Power: 17	please could you explain in details with one example

July 31, 2009, 02:51		#6
shogologo New Member Join Date: May 2009 Posts: 17 Rep Power: 16	Check "CPU and Memory Requirements" section under ANSYS CFX-Solver Manager User's Guide.