Simulation Failed (Memory request)
I have a machine with approximately 600 GB of RAM. However, I can't run simulations with more than 150 Million elements, any tips for what might be happening?
Computing number of non-zeros
Elapsed time for 'Computing number of non-zeros' was 00:00:01 wall clock time.
ERROR: Memory requested 18446744055468834816
Elapsed time for 'Assembling matrix' was 00:00:00 wall clock time.
ERROR: Simulation 'LF' reports an unspecified fatal error! The solver may have run out of RAM.
Don't run for 350 Millions of Elements
Don't run for 194 Millions of Elements
Don't run for 162 Millions of Elements
Run for 144 Millions of elements (94 GB max memory used)
Run for 123 Millions of elements (79 GB max memory used)
Run for 96 Millions of elements (57 GB max memory used)
You are running into the limits of what your OS can allocate RAM per core of your CPU. The solution is to use more processes/cores for this simulation. The pre-requisites are to have enough total RAM for the whole simulation, and enough MPI license tokens. Without any additional tokens, you can use up to two cores of your CPU.
To use MPI parallelization, change Parallelization Handling in the Sovler Properties to Manual, and set the Number of Processes to the desired number of cores.