Class LightArrayRevolverScheduler
- java.lang.Object
-
- org.apache.pekko.actor.LightArrayRevolverScheduler
-
- All Implemented Interfaces:
java.io.Closeable
,java.lang.AutoCloseable
,Scheduler
public class LightArrayRevolverScheduler extends java.lang.Object implements Scheduler, java.io.Closeable
This scheduler implementation is based on a revolving wheel of buckets, like Netty’s HashedWheelTimer, which it advances at a fixed tick rate and dispatches tasks it finds in the current bucket to their respective ExecutionContexts. The tasks are held in TaskHolders, which upon cancellation null out their reference to the actual task, leaving only this shell to be cleaned up when the wheel reaches that bucket next time. This enables the use of a simple linked list to chain the TaskHolders off the wheel.Also noteworthy is that this scheduler does not obtain a current time stamp when scheduling single-shot tasks, instead it always rounds up the task delay to a full multiple of the TickDuration. This means that tasks are scheduled possibly one tick later than they could be (if checking that “now() + delay <= nextTick” were done).
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description protected static class
LightArrayRevolverScheduler.TaskHolder
INTERNAL APIstatic interface
LightArrayRevolverScheduler.TimerTask
INTERNAL API-
Nested classes/interfaces inherited from interface org.apache.pekko.actor.Scheduler
Scheduler.AtomicCancellable, Scheduler.TaskRunOnClose
-
-
Constructor Summary
Constructors Constructor Description LightArrayRevolverScheduler(com.typesafe.config.Config config, LoggingAdapter log, java.util.concurrent.ThreadFactory threadFactory)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description protected long
clock()
Clock implementation is replaceable (for testing); the implementation must return a monotonically increasing series of Long nanoseconds.void
close()
protected scala.concurrent.duration.FiniteDuration
getShutdownTimeout()
Overridable for testsdouble
maxFrequency()
The maximum supported task frequency of this scheduler, i.e.Cancellable
schedule(scala.concurrent.duration.FiniteDuration initialDelay, scala.concurrent.duration.FiniteDuration delay, java.lang.Runnable runnable, scala.concurrent.ExecutionContext executor)
Deprecated API: SeeScheduler.scheduleWithFixedDelay(scala.concurrent.duration.FiniteDuration, scala.concurrent.duration.FiniteDuration, java.lang.Runnable, scala.concurrent.ExecutionContext)
orScheduler.scheduleAtFixedRate(scala.concurrent.duration.FiniteDuration, scala.concurrent.duration.FiniteDuration, java.lang.Runnable, scala.concurrent.ExecutionContext)
.Cancellable
scheduleOnce(scala.concurrent.duration.FiniteDuration delay, java.lang.Runnable runnable, scala.concurrent.ExecutionContext executor)
Scala API: Schedules a Runnable to be run once with a delay, i.e.Cancellable
scheduleWithFixedDelay(scala.concurrent.duration.FiniteDuration initialDelay, scala.concurrent.duration.FiniteDuration delay, java.lang.Runnable runnable, scala.concurrent.ExecutionContext executor)
Scala API: Schedules aRunnable
to be run repeatedly with an initial delay and a fixeddelay
between subsequent executions.scala.concurrent.duration.FiniteDuration
ShutdownTimeout()
protected int
startTick()
Replaceable for testing.scala.concurrent.duration.FiniteDuration
TickDuration()
protected void
waitNanos(long nanos)
Overridable for testsint
WheelSize()
-
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
-
Methods inherited from interface org.apache.pekko.actor.Scheduler
schedule, schedule, schedule, schedule, schedule$default$6, scheduleAtFixedRate, scheduleAtFixedRate, scheduleAtFixedRate, scheduleAtFixedRate, scheduleAtFixedRate$default$6, scheduleOnce, scheduleOnce, scheduleOnce, scheduleOnce, scheduleOnce$default$5, scheduleWithFixedDelay, scheduleWithFixedDelay, scheduleWithFixedDelay, scheduleWithFixedDelay$default$6
-
-
-
-
Constructor Detail
-
LightArrayRevolverScheduler
public LightArrayRevolverScheduler(com.typesafe.config.Config config, LoggingAdapter log, java.util.concurrent.ThreadFactory threadFactory)
-
-
Method Detail
-
WheelSize
public int WheelSize()
-
TickDuration
public scala.concurrent.duration.FiniteDuration TickDuration()
-
ShutdownTimeout
public scala.concurrent.duration.FiniteDuration ShutdownTimeout()
-
clock
protected long clock()
Clock implementation is replaceable (for testing); the implementation must return a monotonically increasing series of Long nanoseconds.
-
startTick
protected int startTick()
Replaceable for testing.
-
getShutdownTimeout
protected scala.concurrent.duration.FiniteDuration getShutdownTimeout()
Overridable for tests
-
waitNanos
protected void waitNanos(long nanos)
Overridable for tests
-
scheduleWithFixedDelay
public Cancellable scheduleWithFixedDelay(scala.concurrent.duration.FiniteDuration initialDelay, scala.concurrent.duration.FiniteDuration delay, java.lang.Runnable runnable, scala.concurrent.ExecutionContext executor)
Description copied from interface:Scheduler
Scala API: Schedules aRunnable
to be run repeatedly with an initial delay and a fixeddelay
between subsequent executions. E.g. if you would like the function to be run after 2 seconds and thereafter every 100ms you would setdelay=Duration(2, TimeUnit.SECONDS)
andinterval=Duration(100, TimeUnit.MILLISECONDS)
.It will not compensate the delay between tasks if the execution takes a long time or if scheduling is delayed longer than specified for some reason. The delay between subsequent execution will always be (at least) the given
delay
. In the long run, the frequency of execution will generally be slightly lower than the reciprocal of the specifieddelay
.If the
Runnable
throws an exception the repeated scheduling is aborted, i.e. the function will not be invoked any more.- Specified by:
scheduleWithFixedDelay
in interfaceScheduler
-
schedule
public Cancellable schedule(scala.concurrent.duration.FiniteDuration initialDelay, scala.concurrent.duration.FiniteDuration delay, java.lang.Runnable runnable, scala.concurrent.ExecutionContext executor)
Description copied from interface:Scheduler
Deprecated API: SeeScheduler.scheduleWithFixedDelay(scala.concurrent.duration.FiniteDuration, scala.concurrent.duration.FiniteDuration, java.lang.Runnable, scala.concurrent.ExecutionContext)
orScheduler.scheduleAtFixedRate(scala.concurrent.duration.FiniteDuration, scala.concurrent.duration.FiniteDuration, java.lang.Runnable, scala.concurrent.ExecutionContext)
.
-
scheduleOnce
public Cancellable scheduleOnce(scala.concurrent.duration.FiniteDuration delay, java.lang.Runnable runnable, scala.concurrent.ExecutionContext executor)
Description copied from interface:Scheduler
Scala API: Schedules a Runnable to be run once with a delay, i.e. a time period that has to pass before the runnable is executed.- Specified by:
scheduleOnce
in interfaceScheduler
-
close
public void close()
- Specified by:
close
in interfacejava.lang.AutoCloseable
- Specified by:
close
in interfacejava.io.Closeable
-
maxFrequency
public double maxFrequency()
Description copied from interface:Scheduler
The maximum supported task frequency of this scheduler, i.e. the inverse of the minimum time interval between executions of a recurring task, in Hz.- Specified by:
maxFrequency
in interfaceScheduler
-
-