ResourceLimiter (Cloud Bigtable HBase Client for Java 1.12.0 API)

com.google.cloud.bigtable.grpc.async

Class ResourceLimiter

• java.lang.Object
• • com.google.cloud.bigtable.grpc.async.ResourceLimiter

• ---

  
  

  public class ResourceLimiter
  extends Object

  This class limits access by RPCs to system resources

  Version:

  $Id: $Id

  Author:

  sduskis

• • Constructor Summary

    Constructors 

    Constructor and Description
    ResourceLimiter(ResourceLimiterStats stats, long maxHeapSize, int maxInFlightRpcs) Constructor for ResourceLimiter.

  • Method Summary

    All Methods Instance Methods Concrete Methods 

    Modifier and Type	Method and Description
    int	getAbsoluteMaxInFlightRpcs() Getter for the field maxInFlightRpcs.
    int	getCurrentInFlightMaxRpcs() Getter for the field currentInFlightMaxRpcs.
    long	getHeapSize() getHeapSize.
    long	getMaxHeapSize() Getter for the field maxHeapSize.
    boolean	hasInflightRequests() hasInflightRequests.
    boolean	isFull() isFull.
    void	markCanBeCompleted(long id) Mark an operation id, as returned by registerOperationWithHeapSize, as complete
    long	registerOperationWithHeapSize(long heapSize) Register an operation with the given size before sending.
    void	setCurrentInFlightMaxRpcs(int currentInFlightMaxRpcs) Setter for the field currentInFlightMaxRpcs.
    void	throttle(int bulkMutationRpcTargetMs) Enable an experimental feature that will throttle requests made from BulkMutation.

    • Methods inherited from class java.lang.Object

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

• • Constructor Detail

    • ResourceLimiter

      public ResourceLimiter(ResourceLimiterStats stats,
                             long maxHeapSize,
                             int maxInFlightRpcs)

      Constructor for ResourceLimiter.

      Parameters:

      maxHeapSize - a long.

      maxInFlightRpcs - a int.

  • Method Detail

    • registerOperationWithHeapSize

      public long registerOperationWithHeapSize(long heapSize)
                                         throws InterruptedException

      Register an operation with the given size before sending. This call WILL BLOCK until resources are available. This method must be paired with a call to markCanBeCompleted in order to make sure resources are properly released.

      Parameters:

      heapSize - The serialized size of the RPC to be sent

      Returns:

      A unique operation id

      Throws:

      InterruptedException - if any.

    • markCanBeCompleted

      public void markCanBeCompleted(long id)

      Mark an operation id, as returned by registerOperationWithHeapSize, as complete

      Parameters:

      id - a long.

    • getMaxHeapSize

      public long getMaxHeapSize()

      Getter for the field maxHeapSize.

      Returns:

      The maximum allowed number of bytes across all across all outstanding RPCs

    • getAbsoluteMaxInFlightRpcs

      public int getAbsoluteMaxInFlightRpcs()

      Getter for the field maxInFlightRpcs.

      Returns:

      The maximum allowed number of in-flight RPCs

    • getCurrentInFlightMaxRpcs

      public int getCurrentInFlightMaxRpcs()

      Getter for the field currentInFlightMaxRpcs.

      Returns:

      The current maximum number of allowed in-flight RPCs

    • setCurrentInFlightMaxRpcs

      public void setCurrentInFlightMaxRpcs(int currentInFlightMaxRpcs)

      Setter for the field currentInFlightMaxRpcs.

    • getHeapSize

      public long getHeapSize()

      getHeapSize.

      Returns:

      The total size of all currently outstanding RPCs

    • isFull

      public boolean isFull()

      isFull.

      Returns:

      true if no more RPCs can be started, false otherwise

    • hasInflightRequests

      public boolean hasInflightRequests()

      hasInflightRequests.

      Returns:

      true if there are currently in-flight RPCs

    • throttle

      public void throttle(int bulkMutationRpcTargetMs)

      Enable an experimental feature that will throttle requests made from BulkMutation. The logic is as follows:

      • To start:
        • reduce parallelism to 25% -- The parallelism is high to begin with. This reduction should reduce the impacts of a bursty job, such as those found in Dataflow.
      • every 20 seconds:

           if (rpc_latency > threshold) {
              decrease parallelism by 10% of original maximum.
           } else if (rpc_latency < threshold && rpcsWereThrottled()) {
              increase parallelism by 5% of original maximum.
           }
         

        NOTE: increases are capped by the initial maximum. Decreases are floored at 1% of the original maximum so that there is some level of throughput.

      Parameters:

      bulkMutationRpcTargetMs - the target for latency of MutateRows requests in milliseconds.