Page 1 of 1

Some questions about Parallel procesing

Posted: Fri Apr 25, 2008 7:50 am
by carlos
Hello,

I have installed MPICH2 on my Core duo labtop running with Windows XP and I also have been checking the presentations of the workshops. I have some doubts about how to run a script with parallel computing.

I'm able to run Opensees.exe an existing script on both processors using:
mpiexec -np 2 opensees.exe example.tcl

I can see on the Windows taks that the two proccessors of the computer are running (at 100%).
If the command is:
mpiexec -np 1 opensees.exe example.tcl

Only 1 processors runs. I must say that both runs spent about 1 minute to complete the analysis.

The command:
mpiexec -np 1 openseesSP.exe example.tcl

runs on the computer, BUT
mpiexec -np 2 openseesSP.exe example.tcl

Fails to do it.

In the last case I have change the sentence system UmfPack with system Mumps -ICNTL14 100 as Frank recommends on this forum but still there are some errors.

The first error is something like:

FEM_ObjectbrokerAllClasses:getCrdTransf3d -- No CrdTransf3d type exist for class tag 6


Questions:

1. There are three (not two) executables availables on the web page:
OpenseesSP.exe
OpenseesMP.exe
I understand the difference between the SP and MP, but what is inside opensees.exe?

2. Do you think that the Parallel version is worthy for running on Labtop computers with two processors, usually not very big models.

3. I have read on one presentation of the workshop that there are some problems with the eigen solver on the OpenseesSP.exe version. Do these problems appear also on the OpenseesMP version?.

4. By the way, Can we expect to have an eigen solver that solve indeterminated systems (rigid body movement). This could help to check models and see if there is one part that is not fixed or linked to others.

5. Are you going to prepare an "example1\main.cpp" for parallel computing ?

Thanks to the Openses team because this seems a big step in the development of Opensees and the "2.0 version" reflects this.

Posted: Fri Apr 25, 2008 9:17 am
by bayram_aygun
Hi,

I downloaded "MPICH2" and "OpenSeesParallel2.0.0.zip" . I installed "MPICH2" to "C:\tcleditor\bin" which is also where all my OpenSees-related files are. After I downloaded "MPICH2" to "C:\tcleditor\bin" I get several folders:

i) "C:\tcleditor\bin\bin"
ii) "C:\tcleditor\bin\examples"
iii) "C:\tcleditor\bin\include"
iv) "C:\tcleditor\bin\jumpshot"
v) "C:\tcleditor\bin\lib"

So, I have my OpenSeesSP, OpenSeesMP, OpenSees 2.0.0 etc., in this same folder: "C:\tcleditor\bin".

0) What do I do next?
1) What is this setting up path variable?
2) I have "smpd.exe" in "C:\tcleditor\bin\bin" and when I click on it nothing happens.

I know that I'm very close to the finish but I need just a little push to get it done.

Thanks for your help,

Posted: Fri Apr 25, 2008 9:44 am
by fmk
Carlos,

1. There are three (not two) executables availables on the web page:
OpenseesSP.exe
OpenseesMP.exe
I understand the difference between the SP and MP, but what is inside opensees.exe?

it is the sequential interpreter.

2. Do you think that the Parallel version is worthy for running on Labtop computers with two processors, usually not very big models.

no .. not unless you are doing parameter studies does it make sense to use the parallel versions.

3. I have read on one presentation of the workshop that there are some problems with the eigen solver on the OpenseesSP.exe version. Do these problems appear also on the OpenseesMP version?.

only if you have a parallel model. if just doing parameter studies no problem.

4. By the way, Can we expect to have an eigen solver that solve indeterminated systems (rigid body movement). This could help to check models and see if there is one part that is not fixed or linked to others.

it's not on my list .. if initially system is supposed to be symmetric positive definite .. using ProfileSPD will result in an error if rigid body modes exist.

5. Are you going to prepare an "example1\main.cpp" for parallel computing ?

i will put it on my listfor when i return from my break.


bayram,

0)
a. you should have installed MPICH2 in the default location, however it should still work. you also need to read the MPICH2 manual.

b. you need to make sure the spmd service is running. type tasklist in the dos shell
and look for the smpd service to see if the install of MPICH2 was successfull in starting the service. if it is not there you need to start it by issuing the command 'smpd -start' in the dos shell. check tasklist to see if it started.

c. then you need to register 'mpiexec -register' in the dos shell..

1) setting the path variable means that when you issue a dos shell command you do not need to be in the directory containing the .exe for it to work providing that directory is in the PATH variable.

2) see 0 above.