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Pony struct for the Pony runtime options C struct that can be used to override the Pony runtime defaults via code compiled into the program.

The way this is done is by adding the following function to your Main actor:

  fun @runtime_override_defaults(rto: RuntimeOptions) =>

and then overriding the fields of rto (the RuntimeOptions instance) as needed.

NOTE: Command line arguments still any values set via @runtime_override_defaults.

The following example overrides the --ponyhelp argument to default it to true instead of false causing the compiled program to always display the Pony runtime help:

actor Main
  new create(env: Env) =>
    env.out.print("Hello, world.")

  fun @runtime_override_defaults(rto: RuntimeOptions) =>
    rto.ponyhelp = true
struct ref RuntimeOptions




new iso create()
: RuntimeOptions iso^


Public fields

var ponymaxthreads: U32 val


Use N scheduler threads. Defaults to the number of cores (not hyperthreads) available. This can't be larger than the number of cores available.

var ponyminthreads: U32 val


Minimum number of active scheduler threads allowed. Defaults to 0, meaning that all scheduler threads are allowed to be suspended when no work is available. This can't be larger than --ponymaxthreads if provided, or the physical cores available.

var ponynoscale: Bool val


Don't scale down the scheduler threads. See --ponymaxthreads on how to specify the number of threads explicitly. Can't be used with --ponyminthreads.

var ponysuspendthreshold: U32 val


Amount of idle time before a scheduler thread suspends itself to minimize resource consumption (max 1000 ms, min 1 ms). Defaults to 1 ms.

var ponycdinterval: U32 val


Run cycle detection every N ms (max 1000 ms, min 10 ms). Defaults to 100 ms.

var ponygcinitial: USize val


Defer garbage collection until an actor is using at least 2^N bytes. Defaults to 2^14.

var ponygcfactor: F64 val


After GC, an actor will next be GC'd at a heap memory usage N times its current value. This is a floating point value. Defaults to 2.0.

var ponynoyield: Bool val


Do not yield the CPU when no work is available.

var ponynoblock: Bool val


Do not send block messages to the cycle detector.

var ponypin: Bool val


Pin scheduler threads to CPU cores. The ASIO thread can also be pinned if --ponypinasio is set.

var ponypinasio: Bool val


Pin the ASIO thread to a CPU the way scheduler threads are pinned to CPUs. Requires --ponypin to be set to have any effect.

var ponyprintstatsinterval: U32 val


Print actor stats before an actor is destroyed and print scheduler stats every X seconds. Defaults to -1 (never).

var ponyversion: Bool val


Print the version of the compiler and exit.

var ponyhelp: Bool val


Print the runtime usage options and exit.