Package org.apache.storm.policy

Interface IWaitStrategy

All Known Implementing Classes:

WaitStrategyPark, WaitStrategyProgressive

public interface IWaitStrategy

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static enum	IWaitStrategy.WaitSituation

Method Summary

Modifier and Type	Method	Description
static IWaitStrategy	createBackPressureWaitStrategy(Map<String,Object> topologyConf)
int	idle(int idleCounter)	Implementations of this method should be thread-safe (preferably no side-effects and lock-free).
void	prepare(Map<String,Object> conf, IWaitStrategy.WaitSituation waitSituation)

Method Details

createBackPressureWaitStrategy

static IWaitStrategy createBackPressureWaitStrategy(Map<String,Object> topologyConf)

prepare

void prepare(Map<String,Object> conf,
 IWaitStrategy.WaitSituation waitSituation)

idle

int idle(int idleCounter)
  throws InterruptedException

Implementations of this method should be thread-safe (preferably no side-effects and lock-free).

Supports static or dynamic backoff. Dynamic backoff relies on idleCounter to estimate how long caller has been idling.

 
  int idleCounter = 0;
  int consumeCount = consumeFromQ();
  while (consumeCount==0) {
     idleCounter = strategy.idle(idleCounter);
     consumeCount = consumeFromQ();
  }
 
 

Parameters:

idleCounter - managed by the idle method until reset

Returns:

new counter value to be used on subsequent idle cycle

Throws:

InterruptedException