View Issue Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0000903||OpenFOAM||[All Projects] Bug||public||2013-06-27 18:10||2014-12-31 19:14|
|Fixed in Version|
|Summary||0000903: blockMesh crashes ("bad set size") when trying too build large meshes with enough RAM|
|Description||First, this bug has been identified with a 2.0.x version of OpenFOAM, on a cluster with the following kernel :|
Linux 184.108.40.206-0.5-default #1 SMP 2011-04-14 10:12:31 +0200 x86_64 x86_64 x86_64
I am working on a fat node of 3TB RAM, allocable through a PBS system.
The problem is that when I try to build with blockMesh a mesh of about 600 millions cells, I get an error message of this kind (extract of the blockMesh log):
Creating points with scale 1
--> FOAM FATAL ERROR:
bad set size -835122496
From function List<T>::setSize(const label)
in file /usr/local/OpenFoam/OpenFOAM-2.0.x/src/OpenFOAM/lnInclude/List.C at line 322.
The full log is given in attachment.
I use here a 1TB RAM request. When I try to make the same mesh but with 4 times less cells with a 250 Gb RAM request, it works without problems. That why I think that it is not a problem of RAM run short.
|Steps To Reproduce||Attached to this report a blockMeshDict file is given. Trying to build a mesh with blockMesh on the basis of this blockMeshDict with at least 575 GB RAM (the amount of RAM needed according to Wyldkcat, see http://www.cfd-online.com/Forums/openfoam-meshing/110655-bad-setsize-while-building-up-too-large-mesh.html#post435489), will lead to the reported bug (at least with OF.2.0.x).|
|Additional Information||Such large meshes would be very helpful for modelling in geosciences, that's why the solving of this bug would be of scientifical interest.|
|Tags||No tags attached.|
blockMeshBug.tar (10,752 bytes)
This seems related to this bug report: http://www.openfoam.org/mantisbt/view.php?id=1033 - In other words, the limit is very likely that the integer (label) variables in OpenFOAM are by default 32-bit, because that saves a lot of RAM for the conventional 64-bit usage.
It's hard to have a system with this much RAM, so it'll probably take a while longer until this is "naturally" fixed.
Let me do some more number crunching on this:
- The attached mesh specifications has a cell count of "3396 3396 50", which equates to 576,640,800 cells.
- It should have around "3397 3397 51" vertexes, which is 588,520,059 points.
- Face count... uhm... too lazy to do proper mathematics on this, but somewhere between 4 and 6 times the number of cells. This would equate to a number between 2,306,563,200 and 3,459,844,800. In comparison to 2^31 = 2,147,483,648
Yep, I guess the mystery is solved... it's the face count that broke the mesh generation. Again, this should be fixed when http://www.openfoam.org/mantisbt/view.php?id=1033 is fixed.
Resolved by commit 2a614865fff303855db7403e145452f909e23ffa
||File Added: blockMeshBug.tar|
|2014-12-29 15:31||wyldckat||Note Added: 0003399|
|2014-12-31 19:14||henry||Note Added: 0003428|
|2014-12-31 19:14||henry||Status||new => resolved|
|2014-12-31 19:14||henry||Resolution||open => fixed|
|2014-12-31 19:14||henry||Assigned To||=> henry|