kernels.harness.default_max_workers()
Worker-pool size when the caller does not choose one: the
Usage
kernels.harness.default_max_workers()IBNR_MAX_WORKERS env var (the container-level control - inside a cpu-limited container os.cpu_count() still reports the HOST’s cores, so an orchestrator should set this alongside --cpus), else all schedulable CPUs, leaving one for the parent and the OS.