RateLimitedDispatcher

public final class RateLimitedDispatcher : RateLimitedDispatcherBase

A PromiseKit Dispatcher that dispatches X closures every Y seconds, on average.

This implementation is O(1) in both space and time, but it uses approximate time accounting. Over the long term, the rate converges to a rate of X/Y, but the transient burst rate will be up to 2X/Y in some situations.

For a completely accurate rate limiter that dispatches as rapidly as possible, see StrictRateLimitedDispatcher. That implementation requires additional storage.

Executions are paced by start time, not by completion, so it’s possible to end up with more than X closures running concurrently in some circumstances.

There is no guarantee that you will reach a given dispatch rate. There are not an infinite number of threads available, and GCD scheduling has limited accuracy.

100% thread safe.

  • A PromiseKit Dispatcher that dispatches X executions every Y seconds, on average.

    This version is O(1) in space and time but uses an approximate algorithm with burst rates up to 2X per Y seconds. For a more accurate implementation, use StrictRateLimitedDispatcher.

    Declaration

    Swift

    override public init(maxDispatches: Int, perInterval interval: TimeInterval, queue: Dispatcher = DispatchQueue.global())

    Parameters

    maxDispatches

    The number of executions that may be dispatched within a given interval.
    perInterval

    The length of the reference interval, in seconds.
    queue

    The DispatchQueue or Dispatcher on which to perform executions. May be serial or concurrent.

  • Undocumented

    Declaration

    Swift

    public convenience init(maxDispatches: Int, perInterval interval: TimeInterval, queue: DispatchQueue)