No times selected after successful parallel run
 

Greetings,

I have spent some time familiarizing myself with OpenFoam after spending a good amount of time with Fluent. I was able to decompose a domain for 32 processors and successfully load up all 8 "processors" on my local machine, plus 8 on each of 3 more machines connected via ethernet.

Everything looked great, no errors during simulation. After it completed, I tried to reconstructPar, only to be given this:

--> FOAM FATAL ERROR:
No times selected

From function reconstructPar
in file reconstructPar.C at line 139.

FOAM exiting

I have searched around, but most of the problems are actually getting the parallel runs working, and I couldn't find a solution to this.

Any insights?

Thanks!

Hi Edwin,

You have to specify which time-steps you want to reconstruct. You can either use -latestTime or specify -time as defined here: http://www.openfoamwiki.net/index.ph...ection_Options

Thanks for that!

So I think there is still a problem. As I mentioned, I am on one computer, lets say "A", and I have three slave machines "B-D." The simulations are run on all 8 cores of each of the four machines.

When I look at the output data from the runs, I notice each machine only has a fourth of the final output data, which is essentially what I expect:

If I log into "B", and look through the directories, I notice that processor0 folder has all the time step data output folders. processor1 only has 0 and constant subdirectories, same with processor2 and 3 folders. Then processor4 folder has all the data in it again. This is mimicked across all four machines. Each one, including the master "A," only has its own data.

What I expected was that each machine would transfer its output back to the master machine. However, I believe I am approaching that a bit wrong. When I manually merge the folders back onto the master, and do a reconstructPar, it reconstructs it pretty well, except for a different problem which I'll post about separately.

So, do I need to setup an NFS share? I hadn't done it simply because I thought everything could be communicated well enough over ssh. I am not against setting one up, just didn't want to waste any time.

Thanks so much!

I'm experiencing exactly the same problem... Waiting for replies.

Vitor

hello,

The simples way is to setup a nfs (or sshfs) file system.

But you can go without. You should setup in your decomposeParDict:
distributed yes;
roots
4 <- nbr of node)
(
/path/for/machine1/case
/path/for/machine2/case
...
)
In this case, the data is local to the machine, so less I/O through the network.

NB: in fact, if you use Paraview for post processing, you can load all the data from each node without recontructing, and post process all .

regards,
olivier