CHANGES.md

Release v0.17.0

• Changes in Async:

  • Fix a segfault that occasionally manifests in the pingpong benchmark

• Changes in Async_rpc:

  • Add a new version of the Async_rpc wire protocol:
    • Clients and servers now exchange Versioned_rpc menus up-front instead of needing to request it via a special RPC, and bin shape digests are included in the menu to allow for clients and servers to check compatibility at runtime.
    • Clients and servers can exchange a user-provided identification string
    • Authorization_failure was added as an additional structured RPC error type, as well as Unknown to cover future cases
  • Add an argument to rpc creator functions to specify how Async_rpc should determine whether the result of the RPC was a success or error. This information is exposed in Tracing_event.t's via Async_rpc_kernel.Async_rpc_kernel_private.Connection.events, which is intended to be used by observability libraries to generate metrics and traces from RPC activity.
  • Add a note in Rpc_transport pointing out that reducing reader/writer buffer sizes can have unexpected effects due to differences in how the the buffers get allocated if they're under or over the threshold to use mmap.
  • Add Connection.serve_unix for serving specifically on unix domain sockets which supports extracting the peer's credentials for authentication.
  • Add the ability to enable dumping RPC message buffers on deserialization errors. This functionality is intended to help debugging cases where invalid messages are being received on an RPC connection and where it's unclear where the corruption is happening.
  • Mention the ASYNC_RPC_MAX_MESSAGE_SIZE env var in the error messages for overly large messages.
  • Fix a bug where an exception getting raised from trying to write an response would get caught and attempted to be written again as an error instead of allowing it to propagate to close the connection.

• Changes in Async_quickcheck:

  • Added Async_quickcheck.async_test_or_error, for getting a Result.t` with the failing input and the error when the test fails.

• Changes in Persistent_connection:

  • Take Event out of the functor and parameterize it so that it's easier to write generic functions that operate on events.
  • Add Make' which allows for using a custom error type instead of Error.t.

• Changes in Unpack_sequence:

  • Allow specifying a size_budget for the pipe when calling Unpack_sequence.unpack_into_pipe.

Release v0.16.0

• Update Async_command.with_options:

  • Add optional behave_nicely_in_pipeline parameter
  • If true, calls Writer.behave_nicely_in_pipeline() when the command starts
  • Default value is true

• Update Async_quickcheck.async_test function:

  • Add optional sizes parameter to specify a sequence of sizes for generated test data
  • Add optional shrinker parameter to provide a custom shrinker for the test data
  • Add optional shrink_attempts parameter to control the number of attempts at shrinking test data

• Changes in Async_rpc.Rpc:

• Change handshake_timeout parameter type from Time.Span.t to Time_float.Span.t.
• Remove on_handshake_error type from Rpc.Connection to simplify the interface

• Changes in Async_rpc.Rpc_transport:

  • Add writer_buffer_size parameter to Rpc_transport.of_fd

• Add new function to Rpc_transport_low_latency.Reader.With_internal_reader:

  • read_one_message_bin_prot_without_buffering
    • Similar to Rpc_kernel.Transport.Reader.read_one_message_bin_prot
    • Reads only the necessary bytes for a single bin prot message from the underlying file descriptor

• Changes in Lock_file_async.Flock:

  • Flock.lock_exn and Flock.lock now have optional exclusive and close_on_exec parameters
    • exclusive controls exclusive access to the lock
    • close_on_exec specifies whether to close the lock when executing a new program

• Update functions in Flock module in Lock_file_async:

  • Added an optional exclusive parameter, enabling shared locks when set to false (previously exclusive locks only)
  • Add optional close_on_exec parameter to control if the lock is closed on exec

• Changes in Persistent_connection:

  • retry_delay and handshake_timeout changed from Time.Span.t to Time_float.Span.t

• Changes in Unpack_sequence:

  • Added a new function: Unpack_sequence.unpack_iter_with_pushback
    • Similar to unpack_iter, but waits for pushback after unpacking every chunk

Old pre-v0.15 changelogs (very likely stale and incomplete)

git version

• Added a new (single-module) library async.log_extended, extending Async.Log with Console and Syslog submodules.

• Improved Async scheduler fairness by calling Thread.yield every cycle, which releases the OCaml lock if any other OCaml threads are waiting to acquire it.

• Added a new (single-module) library async.unpack_sequence, for efficiently unpacking a sequence of packed values coming from a string Pipe.Reader.t or a Reader.t.

• Increased Unix.listen's default backlog from 10 to 64, to reduce occurrences of TCP clients getting Unexpected EOF errors when the listening server is busy.

• Added an optional argument to Pipe functions fold and iter so they can consider a value flushed when it is processed by the supplied ~f rather than when it is read out of the pipe.

• Weak_hashtbl was moved into its own library Weak_hashtbl_async, which is released as part of the async package.

• Added function Tcp.Server.close_finished_and_handlers_determined.

v0.10

• Moved Persistent_connection to Async_kernel, so that it can be used in javascript.

• Improved Log.Output to write, flush, rotate, or close all Log.Output.ts, even if one raises

• Added Async.print_s for pretty printing a sexp to stdout.

• Removed a per-cycle allocation from the scheduler.

• Fixed Reader.load_bin_prot to always return Error when there is an error, rather than return Error in some situations and raise in others.

• Improved the behavior of shutdown when there are errors.

• Added Scheduler.may_sleep_for_thread_fairness, an opt-in configuration that improves thread fairness.

• Added to Sys.file_exists function a follow_symlinks optional argument.

• Fixed the Async scheduler so that for top-level unhandled exceptions, it runs at_exit functions once, not twice.

• For Writer.open_file, exposed the syscall optional argument.

• Exposed Async.ifprintf, which had previously been mistakenly shadowed even though it doesn't block.

• Unified Synchronous_time_source.t and Time_source.t, into a single data structure, allowing one to convert between them as needed. This involved substantive changes to Async's clock.

• Added function Time_source.timing_wheel_now.

• Added stable types for Log.Level and Log.Output.format.

• Improved shutdown function so that when shutdown is forced (i.e. at_shutdown handlers time out), it calls Pervasives.exit, which runs at_exit handlers. This improves Command.async in this situation, due to its use of an at_exit handler to print errors.

• Improved Process.run's error message when working_dir is missing.

• Fixed Rpc.Connection.create so that it doesn't raise on a failed handshake.

• Significantly improved the performance of Log.printf when the log message won't be printed, by using ifprintf to avoid constructing the message.

• Added Socket.Address functions Inet.to_sockaddr and Unix.to_sockaddr, the type specialized versions of Socket.Address.to_sockaddr.

• Added Socket.bind_inet, which is like bind, but restricted to Inet addresses and does not return a Deferred.t. Changed Udp.bind and bind_any to not return a Deferred.t.

• Added to File_tail.create an optional ?throttle argument so that one can use a custom throttle and max_concurrent_jobs rather than a global throttle with a fixed max_concurrent_jobs.

• Renamed Tcp and Rpc's via_local_interface and via_local_port arguments as bind_to_address and bind_to_port.

• Made Tcp.Server.create and create_sock's ~on_handler_error argument mandatory.

• In Tcp.Server, stopped calling on_handler_error for Writer error from inner_monitor, which only indicated that the client likely closed the connection before all the bytes could be written.

• Renamed Command.async as async_spec and Command.async' as async. We want to encourage the use of Command.Param and discourage the use of Command.Spec.

• Changed Async so that in tests it uses synchronous output.

• Changed Async's default max number of open file descriptors from 8_192 to the minimum of 32_768 and ulimit -n -H.

• In the Async scheduler's main loop, avoided calling Time_ns.now and Linux_ext.Timerfd.set_after unless they are needed. This saves about 50ns per cycle.

• Moved Tcp functions for specifying where to connect and where to listen into submodules: Where_to_connect and Where_to_listen

• Changed Tcp.to_host_and_port from taking a string and int to Tcp.Where_to_connect.of_host_and_port, taking a Host_and_port.t

• Changed Rpc.Connection.client to take a Tcp.Where_to_connect.t instead of ~host ~port.

• Changed Synchronous_time_source.Event.abort to return a variant type, in the same style as Time_source.Event.abort. Added abort_exn and abort_if_possible, also in the same style as Time_source.Event.

• Added function Scheduler.long_cycles, which returns the stream of cycles whose duration exceeds a user-supplied time span. This is more efficient than cycle_times, because it only allocates a stream element when there is a long cycle, rather than on every cycle.

• Made internal libraries stdless: Async_unix, Async_extra.

• Changed Udp.recvfrom_loop and read_loop functions to return a variant Closed | Stopped rather than unit.

• Extended the Unix.Inet_addr module's interface to include Core.Unix.Inet_addr's interface.

v0.9

113.43.00

• Added some expect tests of Monitor, in particular Monitor.handle_errors.

• Added a benchmark of Monitor.try_with.

113.33.00

Keep up to date with interface changes in Async_kernel, Async_extra and Async_unix.

113.24.00

Keep up to date with interface changes in Async_kernel, Async_extra and Async_unix.

113.00.00

• Added Async.Std.Printf module so that one doesn't unintentionally use blocking Core.Std.Printf functions in an Async program.

  There was much pre-existing code that did this via:

  : open Core.Std : open Async.Std

  Async.Std.Printf defines blocking functions (e.g printf, eprintf) to cause a type error, but leaves Async-friendly functions (e.g. sprintf, ksprintf) untouched.

  Replaced uses of Printf.*, with Core.Std.Printf.* where needed.

112.35.00

• Include some previously-omitted benchmarks

112.24.00

Keep up to date with interface changes in Async_kernel, Async_extra and Async_unix.

112.17.00

Added tests and updated examples

112.01.00

• update tests

111.25.00

• add a dns example

111.11.00

• Updated the sound.ml example

109.53.00

• Bump version number

109.14.00

• Added function Monitor.kill, which kills a monitor and all its descendants.

  This prevents any jobs from ever running in the monitor again.

109.09.00

• Switched Async.Std's toplevel bindings for Deferred.Or_error's bind and map to use Deferred.Result. This allows them to be used with any 'error type, rather than just Error.t.

109.05.00

• Added val _squelch_unused_module_warning_ to Async.Std.