Module `Sarek_interp.Cpu_domain_pool`

The block pool shared by the parallel interpreter and the Native CPU runtime: worker domains taking tasks from one queue. Created on the first launch and retired when idle (see Cpu_pool_lifecycle).

Each launch waits for its own tasks only and receives only their errors, so concurrent launches from several domains do not interfere.

The launching domain runs the launch's tasks that no worker has taken yet while it waits. A launch from inside a task (a nested launch: an interpreter or Sarek_cpu_runtime.run_parallel kernel, barrier-free or with barriers, that launches again on this pool) therefore completes at any pool size, including a single worker. This holds for this pool only: the Native thread and parallel pools refuse a launch from their own kernels.

type task = unit -> unit

val run : int -> (int -> unit) -> unit

run n f runs f 0 .. f (n - 1) on the pool, in any order and in parallel, and returns when all have run, re-raising the first exception one of them raised. n <= 0 runs nothing and creates no pool.