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Author Topic: Problem with mesh assignment  (Read 4910 times)

jmh

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Problem with mesh assignment
« on: April 22, 2015, 12:44:58 am »

Hello !!!
I'm new user of Pyrosim and FDS...
I try to make a calculation with 2 meshes on 2 computers, but impossible to assign each mesh to each computer...
Mesh01 and mesh02 are assigned on the same computer.
Could you help me ?
If it can help, I did just now a new test :
only 2 meshes... nothing else... Impossible to assign 1st mesh to 1st computer, and 2nd mesh to 2nd computer... Why ?
Maybe because I use the trial version ?  :-[
« Last Edit: April 22, 2015, 05:40:51 am by jmh »
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Charlie Thornton

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Re: Problem with mesh assignment
« Reply #1 on: April 22, 2015, 08:09:08 am »

You should change the number of processes column to 1 for both machines. That controls how many meshes/processes are run on each machine.
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jmh

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Re: Problem with mesh assignment
« Reply #2 on: April 23, 2015, 12:58:04 am »

It works !!!  :)
Thank you very much for the very helpful information...  :D
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jmh

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Number of processors
« Reply #3 on: April 23, 2015, 05:17:57 am »

Even if the calculation works on the 2 computers, something seems strange... :-\
I launch the calculation from a workstation which has 8 processors, and I want also use my laptop which has 4 processors.
I can not set "4" processors in the table for the laptop, only "1" is permitted...
And the calculation is 1.5 longer than the same one with one mesh...
Is that normal ?
« Last Edit: April 23, 2015, 07:09:17 am by jmh »
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Charlie Thornton

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Re: Problem with mesh assignment
« Reply #4 on: April 23, 2015, 08:16:59 am »

Cluster simulations are much slower than simulations that are run on a single computer (communication overhead). The advantage of cluster is being able to run problems that cannot be run on a single machine.

Could you post a screenshot? Even if your laptop had only one core, the dialog should still permit you to run additional meshes on that machine.
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jmh

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Re: Problem with mesh assignment
« Reply #5 on: April 23, 2015, 09:06:58 am »

A screenshot of the cores of each computer ?
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Charlie Thornton

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Re: Problem with mesh assignment
« Reply #6 on: April 23, 2015, 10:07:37 am »

A screenshot of PyroSim's Cluster dialog where you are struggling to change the number of processes. I suspect there is a problem there.
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jmh

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Re: Problem with mesh assignment
« Reply #7 on: April 23, 2015, 10:16:48 am »

Like this ?
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Charlie Thornton

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Re: Problem with mesh assignment
« Reply #8 on: April 23, 2015, 11:18:17 am »

Here is a video of me editing the number of processes:

http://www.screencast.com/t/xOxY9wCIq

Is something preventing you from editing the processes for the laptop? When you say only "1" is permitted, what is PyroSim doing to stop you?
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jmh

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Re: Problem with mesh assignment
« Reply #9 on: April 24, 2015, 01:18:55 am »

When I want to write 2 or 3 or 4 in the column "Number of processes" for host "lt0pk0gg2l", "mesh02" moves automatically to "mesh01"
That happened yesterday...
Tomorrow, it's quite different...
But it's clear that calculations with 2 computers are slower than with only one, so I will stop with 2 computers and continue with only one.
Thank you for your help and time spent for me.... :)
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