org.agrona.concurrent

Class ControllableIdleStrategy

java.lang.Object

org.agrona.concurrent.ControllableIdleStrategy

All Implemented Interfaces:

IdleStrategy

public final class ControllableIdleStrategy
extends Object
implements IdleStrategy

IdleStrategy which can be controlled by a counter so its mode of operation can be switched between doing nothing (NOOP), busy spinning by calling ThreadHints.onSpinWait(), yielding by calling Thread.yield(), or sleeping for the minimum period by calling LockSupport.parkNanos(long) when work count is zero so it idles.

Field Summary

Fields

Modifier and Type	Field and Description
static String	ALIAS Name to be returned from alias().
static int	BUSY_SPIN Apply BusySpinIdleStrategy.
static int	NOOP Apply NoOpIdleStrategy.
static int	NOT_CONTROLLED Not controlled so will go with default of PARK.
static int	PARK Apply SleepingIdleStrategy with minimum sleep interval.
static int	YIELD Apply YieldingIdleStrategy.

Constructor Summary

Constructors

Constructor and Description
ControllableIdleStrategy(StatusIndicatorReader statusIndicator) Configure idle strategy taking an indicator of which strategy should be applied.

Method Summary

Modifier and Type	Method and Description
String	alias() Simple name by which the strategy can be identified.
void	idle() Perform current idle action (e.g.
void	idle(int workCount) Idle based on current status indication value
void	reset() Reset the internal state in preparation for entering an idle state again.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

ALIAS

public static final String ALIAS

Name to be returned from alias().

See Also:

Constant Field Values

NOT_CONTROLLED

public static final int NOT_CONTROLLED

Not controlled so will go with default of PARK.

See Also:

Constant Field Values

NOOP

public static final int NOOP

Apply NoOpIdleStrategy.

See Also:

Constant Field Values

BUSY_SPIN

public static final int BUSY_SPIN

Apply BusySpinIdleStrategy.

See Also:

Constant Field Values

YIELD

public static final int YIELD

Apply YieldingIdleStrategy.

See Also:

Constant Field Values

PARK

public static final int PARK

Apply SleepingIdleStrategy with minimum sleep interval.

See Also:

Constant Field Values

Constructor Detail

ControllableIdleStrategy

public ControllableIdleStrategy(StatusIndicatorReader statusIndicator)

Configure idle strategy taking an indicator of which strategy should be applied.

Parameters:

statusIndicator - indicator of which strategy should be applied.

Method Detail

idle

public void idle(int workCount)

Idle based on current status indication value

Specified by:

idle in interface IdleStrategy

Parameters:

workCount - performed in last duty cycle.

See Also:

IdleStrategy.idle(int)

idle

public void idle()

Perform current idle action (e.g. nothing/yield/sleep). To be used in conjunction with IdleStrategy.reset() to clear internal state when idle period is over (or before it begins). Callers are expected to follow this pattern:

 
 while (isRunning)
 {
   if (!hasWork())
   {
     idleStrategy.reset();
     while (!hasWork())
     {
       if (!isRunning)
       {
         return;
       }
       idleStrategy.idle();
     }
   }
   doWork();
 }
 
 

Specified by:

idle in interface IdleStrategy

reset

public void reset()

Reset the internal state in preparation for entering an idle state again.

Specified by:

reset in interface IdleStrategy

toString

public String toString()

Overrides:

toString in class Object

alias

public String alias()

Simple name by which the strategy can be identified.

Specified by:

alias in interface IdleStrategy

Returns:

simple name by which the strategy can be identified.