Package com.linkedin.venice.throttle

Class EventThrottler

java.lang.Object
com.linkedin.venice.throttle.EventThrottler
All Implemented Interfaces:
VeniceRateLimiter
Direct Known Subclasses:
VeniceAdaptiveIngestionThrottler
public class EventThrottler extends Object implements VeniceRateLimiter
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 Details

  • Constructor Details

    • EventThrottler

      public EventThrottler()

    • EventThrottler

      public EventThrottler(long maxRatePerSecond)
      Parameters:
      maxRatePerSecond - Maximum rate that this throttler should allow (-1 is unlimited)

    • EventThrottler

      public EventThrottler(long maxRatePerSecond, 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, 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, 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(LongSupplier maxRatePerSecondProvider, long intervalMs, 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, LongSupplier maxRatePerSecondProvider, long intervalMs, 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 Details

    • 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()

    • tryAcquirePermit

      public boolean tryAcquirePermit(int units)
      Description copied from interface: VeniceRateLimiter
      Try to acquire permit for the given rcu. Will not block if permit is not available.
      Specified by:
      tryAcquirePermit in interface VeniceRateLimiter
      Parameters:
      units - Number of units to acquire.
      Returns:
      true if permit is acquired, false otherwise.

    • setQuota

      public void setQuota(long quota)
      Description copied from interface: VeniceRateLimiter
      The following methods are used only when checking if the new quota requests are different from the existing quota.
      Specified by:
      setQuota in interface VeniceRateLimiter

    • getQuota

      public long getQuota()
      Specified by:
      getQuota in interface VeniceRateLimiter

    • toString

      public String toString()
      Overrides:
      toString in class Object