Package com.linkedin.venice.throttle

Class EventThrottler

java.lang.Object

com.linkedin.venice.throttle.EventThrottler

public class EventThrottler
extends java.lang.Object

A class to throttle Events to a certain rate This class takes a maximum rate in events/sec and a minimum interval over which to check the rate. The rate is measured over two rolling windows: one full window, and one in-flight window. Each window is bounded to the provided interval in ms, therefore, the total interval measured over is up to twice the provided interval parameter. If the current event rate exceeds the maximum, the call to maybeThrottle(double) will handle this case based on the given throttling strategy. This is a generalized IoThrottler as it existed before, which can be used to throttle Bytes read or written, number of entries scanned, etc.

Field Summary

Fields

Modifier and Type	Field	Description
static EventThrottlingStrategy	BLOCK_STRATEGY
static EventThrottlingStrategy	REJECT_STRATEGY

Constructor Summary

Constructors

Constructor	Description
EventThrottler(long maxRatePerSecond)
EventThrottler(long maxRatePerSecond, long intervalMs, java.lang.String throttlerName, boolean checkQuotaBeforeRecording, EventThrottlingStrategy throttlingStrategy)
EventThrottler(long maxRatePerSecond, java.lang.String throttlerName, boolean checkQuotaBeforeRecording, EventThrottlingStrategy throttlingStrategy)
EventThrottler(io.tehuti.utils.Time time, long maxRatePerSecond, long intervalMs, java.lang.String throttlerName, boolean checkQuotaBeforeRecording, EventThrottlingStrategy throttlingStrategy)
EventThrottler(io.tehuti.utils.Time time, java.util.function.LongSupplier maxRatePerSecondProvider, long intervalMs, java.lang.String throttlerName, boolean checkQuotaBeforeRecording, EventThrottlingStrategy throttlingStrategy)
EventThrottler(java.util.function.LongSupplier maxRatePerSecondProvider, long intervalMs, java.lang.String throttlerName, boolean checkQuotaBeforeRecording, EventThrottlingStrategy throttlingStrategy)

Method Summary

Modifier and Type	Method	Description
protected long	getConfiguredMaxRatePerSecond()
long	getMaxRatePerSecond()
protected io.tehuti.metrics.MetricConfig	getRateConfig()
protected io.tehuti.utils.Time	getTime()
protected boolean	isCheckQuotaBeforeRecording()
void	maybeThrottle(double eventsSeen)	Sleeps if necessary to slow down the caller.

Methods inherited from class java.lang.Object

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

Field Detail

BLOCK_STRATEGY

public static final EventThrottlingStrategy BLOCK_STRATEGY

REJECT_STRATEGY

public static final EventThrottlingStrategy REJECT_STRATEGY

Constructor Detail

EventThrottler

public EventThrottler(long maxRatePerSecond)

Parameters:

maxRatePerSecond - Maximum rate that this throttler should allow (-1 is unlimited)

EventThrottler

public EventThrottler(long maxRatePerSecond,
                      java.lang.String throttlerName,
                      boolean checkQuotaBeforeRecording,
                      EventThrottlingStrategy throttlingStrategy)

Parameters:

maxRatePerSecond - Maximum rate that this throttler should allow (-1 is unlimited)

throttlerName - if specified, the throttler will share its limit with others named the same if null, the throttler will be independent of the others

throttlingStrategy - the strategy how throttler handle the quota exceeding case.

checkQuotaBeforeRecording - if true throttler will check the quota before recording usage, otherwise throttler will record usage then check the quota.

EventThrottler

public EventThrottler(long maxRatePerSecond,
                      long intervalMs,
                      java.lang.String throttlerName,
                      boolean checkQuotaBeforeRecording,
                      EventThrottlingStrategy throttlingStrategy)

Parameters:

maxRatePerSecond - Maximum rate that this throttler should allow (-1 is unlimited)

intervalMs - Minimum interval over which the rate is measured (maximum is twice that)

throttlerName - if specified, the throttler will share its limit with others named the same if null, the throttler will be independent of the others

checkQuotaBeforeRecording - if true throttler will check the quota before recording usage, otherwise throttler will record usage then check the quota.

throttlingStrategy - the strategy how throttler handle the quota exceeding case.

EventThrottler

public EventThrottler(io.tehuti.utils.Time time,
                      long maxRatePerSecond,
                      long intervalMs,
                      java.lang.String throttlerName,
                      boolean checkQuotaBeforeRecording,
                      EventThrottlingStrategy throttlingStrategy)

Parameters:

time - Used to inject a Time in tests

maxRatePerSecond - Maximum rate that this throttler should allow (-1 is unlimited)

intervalMs - Minimum interval over which the rate is measured (maximum is twice that)

throttlerName - if specified, the throttler will share its limit with others named the same if null, the throttler will be independent of the others

checkQuotaBeforeRecording - if true throttler will check the quota before recording usage, otherwise throttler will record usage then check the quota.

throttlingStrategy - the strategy how throttler handle the quota exceeding case.

EventThrottler

public EventThrottler(java.util.function.LongSupplier maxRatePerSecondProvider,
                      long intervalMs,
                      java.lang.String throttlerName,
                      boolean checkQuotaBeforeRecording,
                      EventThrottlingStrategy throttlingStrategy)

Parameters:

maxRatePerSecondProvider - Provider for maximum rate that this throttler should allow (-1 is unlimited)

intervalMs - Minimum interval over which the rate is measured (maximum is twice that)

throttlerName - if specified, the throttler will share its limit with others named the same if null, the throttler will be independent of the others

checkQuotaBeforeRecording - if true throttler will check the quota before recording usage, otherwise throttler will record usage then check the quota.

throttlingStrategy - the strategy how throttler handle the quota exceeding case.

EventThrottler

public EventThrottler(@Nonnull
                      io.tehuti.utils.Time time,
                      java.util.function.LongSupplier maxRatePerSecondProvider,
                      long intervalMs,
                      java.lang.String throttlerName,
                      boolean checkQuotaBeforeRecording,
                      @Nonnull
                      EventThrottlingStrategy throttlingStrategy)

Parameters:

time - Used to inject a Time in tests

maxRatePerSecondProvider - Provider for maximum rate that this throttler should allow (-1 is unlimited)

intervalMs - Minimum interval over which the rate is measured (maximum is twice that)

throttlerName - if specified, the throttler will share its limit with others named the same if null, the throttler will be independent of the others

checkQuotaBeforeRecording - if true throttler will check the quota before recording usage, otherwise throttler will record usage then check the quota.

throttlingStrategy - the strategy how throttler handle the quota exceeding case.

Method Detail

maybeThrottle

public void maybeThrottle(double eventsSeen)

Sleeps if necessary to slow down the caller.

Parameters:

eventsSeen - Number of events seen since last invocation. Basis for determining whether its necessary to sleep.

getMaxRatePerSecond

public final long getMaxRatePerSecond()

getTime

protected io.tehuti.utils.Time getTime()

getRateConfig

protected io.tehuti.metrics.MetricConfig getRateConfig()

getConfiguredMaxRatePerSecond

protected long getConfiguredMaxRatePerSecond()

isCheckQuotaBeforeRecording

protected boolean isCheckQuotaBeforeRecording()