Why would

OpenBLAS blas_thread_init: pthread_create failed for thread 1 of 2: Operation not permitted

occur in a FROM ubuntu:22.04 container (when it does not occur in other containers or the host machine?)

Things checked:

• ulimit -a | grep max user processes
  • max user processes (-u) 31136
• cat /sys/fs/cgroup/pids/pids.max
  • cat: /sys/fs/cgroup/pids/pids.max: No such file or directory
• docker inspect image_name | grep PidsLimit
  • "PidsLimit": 0,
• docker run ... --env OPENBLAS_NUM_THREADS=2 ...
  • No behaviour change
• docker run ... --env OPENBLAS_NUM_THREADS=1 ...
  • It runs, but our code needs 2 threads, so errors later

Will try to generate a minimal example next and share here