CFD Online Logo CFD Online URL
Home > Forums > OpenFOAM Running, Solving & CFD

OpenMPI causes system crash

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   May 13, 2008, 04:44
Default Hi, I'm trying to perform a s
New Member
Christian Wesemeyer
Join Date: Mar 2009
Posts: 19
Rep Power: 10
wese is on a distinguished road
I'm trying to perform a simulation with about 3.3 Mil. cells.
Because this would take quite a lot of time on a single computer, I've used decomposePar to split it up to 15 pieces (9 PC's), but when I've tried to start the job the entire network crashed and our NFS-Server had to be rebooted.

First I thought, that it's not such a good idea to keep all 15 pieces within the NFS file-system.
So I've distributed it to the specific computers (while doing so I've checked all my steps with the OpenFOAM users manual) and changed the decomposition method from METIS to hierarchical, but when I've tried to restart the job the entire network hung again.

The funny thin is, that everything works fine (nevermind what kind of decomposition I use or if I distribute the data onto several disks or not), when I use less cores for my simulation.

If I use for example 12 cores on 6 or 7 machines everything works well.

During the last weekend I've tried to run this job on 8 nodes (4 computers), but after several hours the job was killed automatically.

What bothers me is, that I don't get any logs or other information, so that I always just can restart everything and hope, that it works well then.
Do you have any idea what causes my problems?
Is there any known problem with openMPI and an odd number of nodes and is it possible to get more information, what went wrong if a simulation fails?

To complete my post:
We work on a 100MBit (particularly 1000MBit) Network with a NFS-Server for the OpenFOAM 1.4.1 installation under SuSE-Linux 10.2. All machines are 64-Bit Intel Core2Duo Computers of nearly the same performance.

Thanks in advance

wese is offline   Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem with openmpi mighelone OpenFOAM Running, Solving & CFD 42 July 18, 2012 14:26
OpenMPI performance vega OpenFOAM Running, Solving & CFD 13 November 27, 2007 02:28
Cant run in parallel on two nodes using OpenMPI CHristofer Main CFD Forum 0 October 26, 2007 09:54
OpenFOAM 14 with OpenMPI 12 fhy OpenFOAM Installation 0 July 12, 2007 18:12
System crash during calculation christian_hausmann OpenFOAM Running, Solving & CFD 8 December 7, 2006 13:33

All times are GMT -4. The time now is 08:19.