Abaqus Explicit parallelization

[Bayram2014]

Dear all,
I have usually run abaqus standard in parallel with the classical cpus = option.
Today, I am trying to do the same for an explicit computation.
I run with:
abaqus job=myjob cpus=2
and I got :
mpirun: Warning one or more remote shell commands exited with non-zero status, which may indicate a remote access problem.

I do not have this problem with abaqus standard which runs fine with the required cpus and even gpus.

Thanks a lot for anu help.
Bay

 

[FEA way]

Which OS do you use and how do you submit this job - any nonstandard machines like cluster, server with remote access and so on ?

 

[Bayram2014]

I have tried on 3 different dell machines with 16, 40, 64 cpus respectively. I am not on a cluster.

 

[Bayram2014]

And under ubuntu 20

 

[FEA way]

Did this error message contain any additional information or just the text cited in your first post ? Or maybe log files were generated and explain some details ?

 

[Bayram2014]

This is my log file. Please notice that When I run abaqus standard everything is fine.
*************
Abaqus JOB expl
Abaqus 6.14-5
Abaqus License Manager checked out the following licenses:
Abaqus/Explicit checked out 12 tokens from Flexnet server lic-abaqus-rech.ensam.eu.
<91 out of 400 licenses remain available>.
Begin Analysis Input File Processor
Mon Jul 5 14:41:17 2021
Run pre
Mon Jul 5 14:48:01 2021
End Analysis Input File Processor
Begin Abaqus/Explicit Packager
Mon Jul 5 14:48:01 2021
Run package
Mon Jul 5 14:48:07 2021
End Abaqus/Explicit Packager
Begin Abaqus/Explicit Analysis
Mon Jul 5 14:48:07 2021
Run explicit
Host key verification failed.^M
mpirun: Warning one or more remote shell commands exited with non-zero status, which may indicate a remote access problem.
Mon Jul 5 14:50:58 2021
Begin State File Translator
Mon Jul 5 14:50:58 2021
Run state
Mon Jul 5 14:50:58 2021
End State File Translator
Begin Selected Results Merger
Mon Jul 5 14:50:58 2021
Run mergeSel
Mon Jul 5 14:50:58 2021
End Selected Results Merger
Abaqus Error: Abaqus/Explicit Analysis exited with an error - Please see the
status file for possible error messages if the file exists.
Abaqus/Analysis exited with errors

 

[FEA way]

Try running this with thread-based parallelization instead of MPI-based one - add this command:
mp_mode=threads

 

[Bayram2014]

Thanks. it works with this option.

 

[Konsti]

Hi and sorry to join the party so late. I've had my own fair share of parallelisation errors, the last one being "domain decomposition error":

I submit my model to the cluster with 5 cores, parallelisation in 5 domains, dynamic load balancing=off (because I have a job restart), mp_mode = threads. It used to work just fine until I defined many surface-surface soft contacts in my model.

Anything very wrong I'm doing here? I don't know how to change to .env files on the cluster, I have sent a separate request to our team for this.

Thank you!

 

[FEA way]

Did you try doing what’s suggested in this error message ? If it doesn’t help then you may have to redefine some of these contacts as they seem to cause problematic overconstraints.

 

[Konsti]

Thank you FEA Way,
I have no idea how to do this, zero experience with overwriting settings using the .env files. I tried: can't find where this variable is and I don't know how to modify it. What does "set to ON" mean? Do I write XPL_LINK_NOMERGE = ON? Or = True?
Abaqus could make our lives much easier...
Konstantinos

 

[Konsti]

Update: loop parallelisation (instead of domain) seems to work, although less efficiently. If anyone has a better way of parallelising (with domains) using the .env settings above, please advise!