Hi Syavash, As Alexandra said - if you can provide the output of the solver on crash that would be extremely helpful to diagnose any issue. In terms of the mesh size - these are small meshes relative to some of meshes we have run internally. Can you provide any details on how you have generated the mesh? I.e: * The meshing software you have used and version number * The cell count and cell types i.e Tris,Quads for 2D or Tet,Prism,Hex for 3D * And your procedure to convert to a Nektar++ mesh file i.e. your process to import to a .xml Additionally the mesh file plus the session file and a description of your case would be useful - as it will help to diagnose the issue. Kind regards, James Slaughter. ________________________________ From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Ehsan Asgari <eh.asgari@gmail.com> Sent: 08 March 2023 17:19 To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] Standard way of handling large mesh in parallel run This email from eh.asgari@gmail.com originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list<https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email stamping for this address. Hi Everyone I've been trying to import a mesh generated in a third-party package and run it in the incompressible solver. First, I tried a smaller mesh with a size of 10MB and 32 cores on an HPC with 3GB ram specified for each core. It worked and I proceeded to the main larger mesh with a size of 75MB and 128 cores. However, I found it can be quite challenging to establish a simulation as I often get MPI-related errors at the very beginning. I was wondering if this is the standard way of handling large mesh files in parallel using mpirun: mpirun -np 128 IncNavierStokesSolver condition.xml grid.xml I am new to nektar++ so my question might seem trivial. Kind regards syavash