moonpool/CHANGES.md

0.5.1

• fix Ws_pool: workers would exit before processing all remaining tasks upon shutdown

0.5

features

• add Bb_queue.transfer -add Bb_queue.to_{iter,gen,seq}

• add Fifo_pool, a simple pool with a single blocking queue for workloads with coarse granularity tasks that value latency (e.g. a web server)

• add a work-stealing pool for heavy compute workloads that feature a lot of await/fork-join, with a lot of help from Vesa Karvonen (@polytypic)

• add Fut.spawn_on_current_runner

• add Runner.{spawn_on_current_runner, await}

• add a few more toplevel aliases in Moonpool itself

• add No_runner: a runner that runs tasks synchronously in the caller

• on shutdown, pools will finish running all present tasks before closing. New tasks are immediately rejected.

• use an optional dependency on thread-local-storage to implement work stealing and spawn_on_current_runner

optimizations

• use the main domain to spawn threads on it. This means we can really use all cores, not all but one.
• in Fork_join.both, only one of the two sides schedules a task, the other runs in the current thread. This reduces scheduling overhead.
• compare to domainslib in benchmarks. With the WS pool we're now slightly ahead in terms of overhead on the recursive fib benchmark.

breaking

• deprecate Pool, now an alias to Fifo_pool

0.4

• add Fut.{reify_error,bind_reify_error}

• full lifecycle for worker domains, where a domain will shutdown if no thread runs on it, after a short delay.

• fix: generalize type of create_arg

• perf: in Bb_queue, only signal condition on push if queue was empty

0.3

• add Fork_join for parallelizing computations. This is only available on OCaml 5.x because it relies on effects.

• add Fork_join.{for_,map_array,map_list}

• add Fork_join.all_{list,init}

• add Pool.with_

• add a channel module

• add Runner, change Pool to produce a Runner.t

• add a Lock module

• add support for domain-local-await when installed

• add Fut.await for OCaml >= 5.0

• fix: Fork_join.both_ignore now has a more general type

• expose Suspend_ and its internal effect with an unstability alert. This is intended for implementors of Runner only.

• port cpp.ml from containers, replace previous codegen with it. This will provide better flexibility for supporting multiple versions of OCaml in the future.

• add Pool.run_wait_block; rename Pool.run into Pool.run_async

• fix: in blocking queue, pop works on a non empty closed queue

0.2

• add Fut.for_list

• add around_task to Pool.create

• add Pool.shutdown_without_waiting

• add Pool.num_tasks

• add Fut.is_done

• add Blocking_queue.size

• add Fut.for_array to easily iterate on an array in parallel

• add Fut.get_or_fail{,_exn}

• perf: limit number of work queues in pool

• perf: use multiple queues and non-blocking work-stealing from them, in pool this improves the behavior for many small tasks by reducing contention on each queue

• fix: fut: actually run all map/bind callbacks in pool if provided

0.1.1

• fix(fut): fix bug when calling wait_list []
• fix: join_array on arrays of length=1 had a bound error

0.1

initial release