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run DELWAQ on a cluster?

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Zhanxian Wang, modified 1 Year ago.

run DELWAQ on a cluster?

Padawan Posts: 35 Join Date: 4/11/12 Recent Posts
Hi, all,

I have a question regarding running DELWAQ on a cluster:

My FLOW model is a 3D z-layer model, and I can run the FLOW model on our cluster on multi-cores using MPI. After switching on "Export WAQ Input" on the FLOW GUI, the FLOW model generates the WAQ related HD files on each sub-domain (e.g. 50 sub-domains if using 50 cores). My question is how can I setup the WAQ model to use these WAQ input files directly and run the WAQ simulation on the cluster?

Thanks,
Jonathan
AM
Arjen Markus, modified 1 Year ago.

RE: run DELWAQ on a cluster?

Jedi Knight Posts: 222 Join Date: 1/26/11 Recent Posts
The short answer is: you can't. DELWAQ does not support this type of multiprocessing.
The somewhat longer answer is: we are working on the possibility to take advantage of multi-cores in the same way that Delft3D-FLOW/D-FLOW-FM can, but that will take some while yet.

For now the best option is to combine the results from the individual domains using ddcouple/ddcouplefm into a single domain.
ZW
Zhanxian Wang, modified 1 Year ago.

RE: run DELWAQ on a cluster?

Padawan Posts: 35 Join Date: 4/11/12 Recent Posts
Arjen,

Thanks again for your quick response.

Is ddcouple available for Linux? So far, I have to copy all of the WAQ coupling files from the cluster to a local Windows machine and run ddcouple there to combine the files.

Thanks,
Jonathan
AM
Arjen Markus, modified 1 Year ago.

RE: run DELWAQ on a cluster?

Jedi Knight Posts: 222 Join Date: 1/26/11 Recent Posts
Hm, that should not be necessary - we use the Linux-version all the time. Let me check this.
Michelle Jeuken, modified 1 Year ago.

RE: run DELWAQ on a cluster?

Jedi Knight Posts: 156 Join Date: 1/21/13 Recent Posts
Here is a Linux version of ddcouple. This works only for Delft3D 4 structured flow. For Delft3D FM runs you should use ddcouplefm.
ZW
Zhanxian Wang, modified 1 Year ago.

RE: run DELWAQ on a cluster?

Padawan Posts: 35 Join Date: 4/11/12 Recent Posts
Thanks Michelle!

To be clear, I can still run DELWAQ on a cluster, but not in the MPI mode, right?

Thanks,
Jonathan
Michelle Jeuken, modified 1 Year ago.

RE: run DELWAQ on a cluster? (Answer)

Jedi Knight Posts: 156 Join Date: 1/21/13 Recent Posts
No, Delwaq can't run in MPI mode, but it can make use of multiple threads on a single node. Add the following line to block 7 of the inp-file:

CONSTANTS nothreads DATA 0.0 ; OMP-parallelism ’on’

Just before #7

Part of the code of Delwaq then makes use of multiple threads when available. Look in the mon-file how many threads were used. The value of 0.0 tries to take as many as available, but you can limit it by giving an specific number.

This will also work on Windows computers