Running Abaqus Standard, Quadcore CPU, Windows 64 bit 1

[agi2007]

Dear collegues,
I'm performing some tests on a Quad core DELL machine, with Windows 64 bit, 16Gb of RAM.
I'm running Abaqus Standard using different cores number (cpus=1, cpus=2, cpus=4). Nothing seems to change in the CPU time (1-2 % of difference....).
Has someone performed similar tests?
Have I to set something of particular in the .env file?

Thanks

ALF

 

[xerf]

Some remarks:

What is your benchmark problem ?

Have you looked at the job duration in the .log file ?

I think you might have to alter the .env file to have
mp_mode = THREADS. (I think for some ABAQUS versions the default value is mp_mode=MPI)

For cpus>1 you need additional licenses available.

You can set the default number of cpus in the .env file.

 

[Yoman]

I was told that a model with large degree of freedom will be more benifit to the muti cpu. what type of analysis did your ran?
Have you try running the brenchmark job downloaded from the abaqus web site?
I think it will benifit if those test is done as many of us may want to buy a quad core computer but not sure if it is value for money. (I am one of it)

Many thanks

 

[agi2007]

Thanks to all.
My model has 2300000 dof. It is not so big, but the CPUs time mainly depends on the severe discontinuity interactions (contact solving). In the WE, I'll test the mp_mode settings like suggested by xerf.
The benchmark job downloaded from the abaqus web site are not interested, they are not "big job"......

PS I.m sure Abaqus takes the command cpus=4, I checked the .msg file

 

[agi2007]

Dear Xerf,
nothing change (some minutes more ...) changing the .env setting as you suggest.
I have no more ideas..........

 

[bassmanjax]

As I understand it, Standard does more calcs 'out-of-core' whereas Explicit does most of the calcs 'in-core'.

What I mean is that Standard reads and writes a lot of data to and from the hard disk during a run, whereas Explicit performs more calculations in memory (cache, RAM). RAM is waayyy faster to read/write than the hard disk.

Could be that you aren't getting a significant gain by using more CPU's on your Standard job and your hard disk speed is slowing you down.

I would try looking at the option 'standard_memory_policy' in the .env file. I've got this set to MAXIMUM, so that Standard will try and do most stuff 'in-core' rather than 'out-of-core'.

Regards

Martin Stokes CEng MIMechE

 

[agi2007]

If you have a lot of RAM, ABAQUS Standard can keep a large amount of files
in the RAM and save up to the 90 % of the computational time.
For the same Job (Abaqus Standard), running on a node with 2 CPUs, Dualcore (so 4 cores maximum)
with LINUX, I obtained the following results:
1 core: 36000 seconds
4 core: 15000 seconds
It seems reasonable.
On a node with 1 CPU, Quadcore but with Windows professional 64 bit:
1 core: 35000 seconds
4 core: 34500 seconds

Is WINDOWS the problem?

PS I'm still using standard_memory_policy=MAXIMUM

 

[xerf]

Wow! Is it XP64 or Vista64 ?

I do have to try this!

 

[agi2007]

XP 64

ciao

 

[agi2007]

I think I foud the problem!!! With the standard installation of windows XP professional x64, isn' t possible to run in MPI!! I think I have to run in MPI (in any case I want to test this opportunity...) to drastically reduce the computational time.
Now: what Have I to install to do this ???

Thanks

 

[xerf]

See this:

http://www.simulia.com/support/v67/Windows_x86-64.html

 

[agi2007]

I have installed MPICH2 and I wrote the executable path in the .env file:
mp_mpirun_path = {NATIVE:'C:\Program Files\MPICH2\mpiexec.exe'}

I obtained the following error:
Abaqus Error: The executable C:\Program
aborted with system error code 65535.

It seems that abaqus doesn't find the MPI executable because
It doesn't recognize the space (between Program and Files) in the executable path.....
How can I give the path??
I can't rename the system directory "Program Files" in "Program_Files".....
Thanks
ALF

 

[johnhors]

try using C:\PROGRA~1\MPICH2\mpiexec.exe