aleph.flow — aleph 0.6.2

acquire clj

(acquire p k)

Acquires an object from the pool for key k, returning a deferred containing the object. May throw a java.util.concurrent.RejectedExecutionException if there are too many pending acquires.

dispose clj

(dispose p k obj)

Disposes of a pooled object which is no longer valid.

fixed-thread-executor clj

(fixed-thread-executor num-threads)

(fixed-thread-executor num-threads options)

Returns an executor which has a fixed number of threads.

instrumented-executor clj

(instrumented-executor {:keys [thread-factory queue-length stats-callback
                               sample-period control-period controller metrics
                               initial-thread-count onto?]
                        :or {initial-thread-count 1
                             sample-period 25
                             control-period 10000
                             metrics (EnumSet/allOf Stats$Metric)
                             onto? true}})

Returns a java.util.concurrent.ExecutorService, using Dirigiste.

|:---|:---- | thread-factory | an optional java.util.concurrent.ThreadFactory that creates the executor's threads. | | queue-length | the maximum number of pending tasks before .execute() begins throwing java.util.concurrent.RejectedExecutionException, defaults to 0. | stats-callback | a function that will be invoked every control-period with the relevant statistics for the executor. | sample-period | the interval, in milliseconds, between sampling the state of the executor for resizing and gathering statistics, defaults to 25. | control-period | the interval, in milliseconds, between use of the controller to adjust the size of the executor, defaults to 10000. | controller | the Dirigiste controller that is used to guide the pool's size. | metrics | an EnumSet of the metrics that should be gathered for the controller, defaults to all. | initial-thread-count | the number of threads that the pool should begin with. | onto? | if true, all streams and deferred generated in the scope of this executor will also be 'on' this executor.

instrumented-pool clj

(instrumented-pool
  {:keys [generate destroy stats-callback max-queue-size sample-period
          control-period controller]
   :or {sample-period 10 control-period 10000 max-queue-size 65536}})

Returns a Dirigiste object pool, which can be interacted with via acquire, release, and dispose.

Param key	Description
generate	a single-arg funcion which takes a key, and returns an object which should be non-equal to any other generated object
destroy	an optional two-arg function which takes a key and object, and releases any associated resources
stats-callback	a function which will be invoked every control-period with a map of keys onto associated statistics
max-queue-size	the maximum number of pending acquires per key that are allowed before acquire will start to throw a java.util.concurrent.RejectedExecutionException.
sample-period	the interval, in milliseconds, between sampling the state of the pool for resizing and gathering statistics, defaults to 10.
control-period	the interval, in milliseconds, between use of the controller to adjust the size of the pool, defaults to 10000.
controller	a Dirigiste controller that is used to gide the pool's size.

release clj

(release p k obj)

Releases an object for key k back to the pool.

utilization-executor clj

(utilization-executor utilization)

(utilization-executor utilization max-threads)

(utilization-executor utilization max-threads options)

Returns an executor which sizes the thread pool according to target utilization, within [0,1], up to max-threads. The queue-length for this executor is always 0, and by default has an unbounded number of threads.