ML_NCSHMEM

ML_NCSHMEM = [integer]
Default: ML_NCSHMEM = Number of available ranks per computational node

Description: Specifies the number of MPI ranks that share a single shared memory segment.

The total number of memory segments created equals the number of cores per node divided by ML_NCSHMEM. All memory segments have identical sizes, so a larger number of segments results in higher total memory consumption.

However, on systems with multiple NUMA domains, performance can degrade significantly during machine-learned force field inference if all domains access the same memory segment. For optimal performance, each NUMA domain should have its own dedicated shared memory segment.

Related tags and articles