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March 6, 2006, 05:58 |
dear all,
i am now solving
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#1 |
Member
VVqf
Join Date: Mar 2009
Location: Braunschweig
Posts: 66
Rep Power: 17 |
dear all,
i am now solving a 2.5e6 cells case with parallel LES. I set the case as a normal non-parallel case, and did not use decomposePar utility. it started running, but then stopped, and got 2 files: mycase.decompout: ... Nprocs : 1 Create time Time = 0 Create mesh Calculating distribution of cells Selecting decompositionMethod metis Finished decomposition in 10.26 s Calculating original mesh data Distributing cells to processors Distributing faces to processors Calculating processor boundary addressing Distributing points to processors Constructing processor meshes Processor 0 Number of cells = 75600 Number of faces shared with processor 30 = 1730 Number of faces shared with processor 5 = 775 Number of faces shared with processor 1 = 2546 Number of faces shared with processor 28 = 309 Number of faces shared with processor 4 = 1343 Number of faces shared with processor 3 = 263 Number of faces shared with processor 2 = 2497 Number of boundary faces = 3065 Processor 1 Number of cells = 74647 ... ... Processor 31 Number of cells = 74255 Number of faces shared with processor 28 = 1979 Number of faces shared with processor 30 = 1844 Number of faces shared with processor 19 = 1637 Number of faces shared with processor 26 = 1033 Number of faces shared with processor 25 = 38 Number of boundary faces = 6027 Processor 0: field transfer Processor 1: field transfer ... ... Processor 32: field transfer End. ... Nprocs : 1 Create time Create mesh Time = 0 Reconstructing FV fields Reconstructing volScalarFields nuTilda nuSgs p k Reconstructing volVectorFields U Reconstructing volTensorFields B No tetFem fields No lagrangian fields End. Removing single processor directories \\end of file mycase.solverout: ... ... [31] Nprocs : 32 Create mesh, no clear-out for time = 0 Reading transportProperties Reading field p Reading field U Reading/calculating face flux field phi Selecting incompressible transport model Newtonian Creating field Umean Creating field R Creating field Bmean Creating field epsilonMean Creating field pMean Creating field pPrime2Mean Reading probeLocations Constructing probes Starting time loop Time = 5e-05 Mean and max Courant Numbers = 0.0520911 4.52888 \\end of file Thank you for reading this long post, and How can I get it run properly? |
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March 6, 2006, 07:11 |
Hi VVqf,
I'm a bit confused
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#2 |
Senior Member
Eugene de Villiers
Join Date: Mar 2009
Posts: 725
Rep Power: 21 |
Hi VVqf,
I'm a bit confused. You say you didn't use decomposePar, but then you show the logs for decomposePar and reconstructPar and your LES code seems to be running in parallel : "[31] Nprocs : 32" I take it your LES run is locking-up/crashing? First thing to do is to lower your timestep to 1e-5 or 5e-6. Then run the case in serial. Really, I need more info to make any useful suggestions. |
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March 6, 2006, 08:12 |
Hi Eugene,
i forgot to ment
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#3 |
Member
VVqf
Join Date: Mar 2009
Location: Braunschweig
Posts: 66
Rep Power: 17 |
Hi Eugene,
i forgot to mention, to run the case i used the command openfoam_hpc-1.2. I was told to do so by our administrator. The whole command is: openfoam_hpc-1.2 -np 32 oodles mycase from the file, i guess, both decomposePar and mpirun are wrapped inside this command. I dont know the detail. and the timestep 5e-05 is ok when running turbulent SST in CFX. I will try you suggestion. thank you. |
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March 6, 2006, 08:28 |
and before when I ran it in se
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#4 |
Member
VVqf
Join Date: Mar 2009
Location: Braunschweig
Posts: 66
Rep Power: 17 |
and before when I ran it in serial(on my own machine), I've got message as follows:
Creating field epsilonMean Creating field pMean Creating field pPrime2Mean Reading probeLocations Constructing probes new cannot satisfy memory request. This does not necessarily mean you have run out of virtual memory. It could be due to a stack violation caused by e.g. bad use of pointers or an out of date shared library Starting time loop Time = 5e-05 Mean and max Courant Numbers = 0.0522919 4.52888 new cannot satisfy memory request. |
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March 6, 2006, 08:55 |
"new cannot satisfy memory req
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#5 |
Senior Member
Eugene de Villiers
Join Date: Mar 2009
Posts: 725
Rep Power: 21 |
"new cannot satisfy memory request" means you have run out of memory. I guess you're personal machine is 32bit? Then 2.6 million cells would be unlikely to run on it. You can try recompiling oodles with averaging disabled, might just allow you to run.
I have no idea what "openfoam_hpc-1.2" does, it must be something thats been cooked up by your sysadmins. As such it is impossible for me to comment on why it is failing. CFX uses a coupled solver, which might be why you can run at higher CFL numbers. The problem is the PISO solver used by oodles in 1.2 will be unstable with central differencing above CFL ~ 0.9. That doesn't mean it will always blow up, but it is quite likely to. To get more info from your runs when they fail add "2>&1" to your log pipe. This should redirect all error messages to the standard output and thence to your log. Ask your sysadmin about this for "openfoam_hpc-1.2". Perhaps you can get some more info this way, because what is currently available is simply not enough to make a diagnosis. |
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