Package com.linkedin.venice.throttle

Class TokenBucket

java.lang.Object

com.linkedin.venice.throttle.TokenBucket

public class TokenBucket
extends java.lang.Object

See Also:

Token Bucket on Wikipedia This implementation aims to be very high performance with the goal of supporting a very large number of TokenBuckets in an application; thus avoiding an auxilliary thread to refill the bucket.

Constructor Summary

Constructors

Constructor	Description
TokenBucket(long capacity, long refillAmount, long refillInterval, java.util.concurrent.TimeUnit refillUnit)
TokenBucket(long capacity, long refillAmount, long refillInterval, java.util.concurrent.TimeUnit refillUnit, java.time.Clock clock)	This constructor should only be used by tests.

Method Summary

Modifier and Type	Method	Description
float	getAmortizedRefillPerSecond()
long	getStaleTokenCount()	This method does not call #update(), so it is only accurate as of the last time #tryConsume() was called
double	getStaleUsageRatio()
boolean	tryConsume()
boolean	tryConsume(long tokensToConsume)

Methods inherited from class java.lang.Object

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

Constructor Detail

TokenBucket

public TokenBucket(long capacity,
                   long refillAmount,
                   long refillInterval,
                   java.util.concurrent.TimeUnit refillUnit,
                   java.time.Clock clock)

This constructor should only be used by tests. Application should not specify it's own instance of Clock

Parameters:

capacity -

refillAmount -

refillInterval -

refillUnit -

clock -

TokenBucket

public TokenBucket(long capacity,
                   long refillAmount,
                   long refillInterval,
                   java.util.concurrent.TimeUnit refillUnit)

Parameters:

capacity - The maximum number of tokens that the bucket can have at any one time. Any refill beyond the capacity is lost. A capacity larger than the refillAmount supports bursting.

refillAmount - The number of tokens added to the bucket each interval

refillInterval - The interval of time between refills of the bucket

refillUnit - The TimeUnit for the refillInterval

Method Detail

getStaleTokenCount

public long getStaleTokenCount()

This method does not call #update(), so it is only accurate as of the last time #tryConsume() was called

Returns:

number of tokens remaining in the bucket

tryConsume

public boolean tryConsume(long tokensToConsume)

tryConsume

public boolean tryConsume()

getAmortizedRefillPerSecond

public float getAmortizedRefillPerSecond()

getStaleUsageRatio

public double getStaleUsageRatio()