Randomized multi-threaded effects based Picos compatible scheduler for OCaml 5.
ℹ️ This scheduler implementation is specifically intended for testing libraries implemented in Picos.
⚠️ This scheduler uses Picos_io_select internally. If running multiple threads that each run this scheduler, Picos_io_select.configure must be called by the main thread before creating other threads.
Picos is an interface that allows schedulers to make scheduling decisions freely. After each effect this scheduler picks the next fiber to run randomly from the collection of ready fibers. This can help to discover bugs in programs implemented in Picos that make invalid scheduling assumptions.
val context : ?fatal_exn_handler:(exn -> unit) -> unit -> tcontext () creates a new context for randomized runners. The context should be consumed by a call of run ~context ....
val runner_on_this_thread : t -> unitrunner_on_this_thread context starts a runner on the current thread to run fibers on the context. The runner returns when run ~context ... returns.
val run_fiber : ?context:t -> Picos.Fiber.t -> (Picos.Fiber.t -> unit) -> unitrun_fiber fiber main runs the main program as the specified fiber and returns main and all of the fibers spawned by main have returned.
The optional context argument specifies a context in which to run the main program. If unspecified, a new context is automatically created and the scheduler will be single-threaded. By creating a context, spawning concurrent or parallel runners on to the context, and then explicitly passing the context to run ~context ... one can create a multi-threaded scheduler. Only a single call of run per context is allowed.
val run : ?context:t -> ?forbid:bool -> (unit -> 'a) -> 'arun main is equivalent to calling run_fiber with a freshly created fiber and main wrapped to capture the result of main.
The optional forbid argument defaults to false and determines whether propagation of cancelation is initially allowed.
val run_fiber_on :
?fatal_exn_handler:(exn -> unit) ->
n_domains:int ->
Picos.Fiber.t ->
(Picos.Fiber.t -> unit) ->
unitrun_fiber_on ~n_domains main spawns n_domains - 1 additional domains and runs the main on the current domain and those additional domains.
val run_on :
?fatal_exn_handler:(exn -> unit) ->
n_domains:int ->
?forbid:bool ->
(unit -> 'a) ->
'arun_on ~n_domains main is equivalent to calling run_fiber_on with a freshly created fiber and main wrapped to capture the result of main.
The optional forbid argument defaults to false and determines whether propagation of cancelation is initially allowed.