Package com.google.cloud.grpc

Class GcpManagedChannelOptions.GcpChannelPoolOptions.Builder

java.lang.Object
com.google.cloud.grpc.GcpManagedChannelOptions.GcpChannelPoolOptions.Builder
Enclosing class:
GcpManagedChannelOptions.GcpChannelPoolOptions
public static class GcpManagedChannelOptions.GcpChannelPoolOptions.Builder extends Object

  • Constructor Details

  • Method Details

    • build

      public GcpManagedChannelOptions.GcpChannelPoolOptions build()

    • setMaxSize

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setMaxSize(int maxSize)
      Sets the maximum size of the channel pool.
      Parameters:
      maxSize - maximum number of channels the pool can have.

    • setMinSize

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setMinSize(int minSize)
      Sets the minimum size of the channel pool. This number of channels will be created and these channels will try to always keep connection to the server established.
      Parameters:
      minSize - minimum number of channels the pool must have.

    • setInitSize

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setInitSize(int initSize)
      Sets the initial channel pool size. This is the number of channels that the pool will start with. If it is less than setMinSize(int) it is ignored.
      Parameters:
      initSize - number of channels to start the pool with.
      Returns:

    • setDynamicScaling

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setDynamicScaling(int minRpcPerChannel, int maxRpcPerChannel, Duration scaleDownInterval)
      Enables dynamic scaling functionality.

      After a call is counted, load above maxRpcPerChannel on its selected channel or across the pool average signals a background scale-up worker.

      Every scaleDownInterval, after consecutive low-load checks, the least-loaded channels are marked draining and removed from selection, bounded by maxScaleDownChannels; fewer affinity bindings and then older allocations break load ties. Draining channels receive no new picks or affinity binds and close after their in-flight calls reach zero and drainIdleGrace elapses. Scale-up always creates new channels.

      Parameters:
      minRpcPerChannel - minimum desired average concurrent calls per channel.
      maxRpcPerChannel - maximum desired average concurrent calls per channel.
      scaleDownInterval - how often to check for a possibility to scale down.

    • disableDynamicScaling

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder disableDynamicScaling()
      Disables dynamic scaling functionality.
      See Also:

    • setScaleUpCooldown

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setScaleUpCooldown(Duration scaleUpCooldown)
      Sets the minimum interval between successful scale-up operations. Zero uses the 10-second default.

    • setScaleDownConsecutiveLowLoadChecks

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setScaleDownConsecutiveLowLoadChecks(int checks)

    • setMaxScaleUpPercent

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setMaxScaleUpPercent(int percent)
      Sets the maximum percentage of active channels added by one scale-up operation. The percentage cap has a two-channel floor before desired-size and maximum-size clamps.

    • setMaxScaleDownChannels

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setMaxScaleDownChannels(int channels)

    • setDrainIdleGrace

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setDrainIdleGrace(Duration drainIdleGrace)
      Sets how long an idle draining channel remains open for sticky affinity references and in-flight calls before its delegate closes. Defaults to one minute.

    • setErrorPenaltyStep

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setErrorPenaltyStep(int errorPenaltyStep)
      Sets the load penalty added after each retryable channel error. A value of 0 disables error penalties. Each step accumulates on the stored undecayed penalty, capped at maxRpcPerChannel. Must not be negative. Defaults to 5.

    • setErrorPenaltyDuration

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setErrorPenaltyDuration(Duration errorPenaltyDuration)
      Sets how long an applied penalty takes to decay linearly to zero. Each new retryable error resets the decay timer to a full window. Must be positive. Defaults to 5 seconds.

    • setChannelPrimer

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setChannelPrimer(@Nullable GcpChannelPrimer channelPrimer)
      Sets the optional hook that primes newly built scale-up channels concurrently. Only channels added by dynamic scale-up are primed; the initial pool and non-dynamic growth are published as soon as they are built. Each scale-up channel is published individually when its own primer future succeeds. A null primer disables priming and preserves the existing scale-up path.

    • setChannelPrimeTimeout

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setChannelPrimeTimeout(Duration channelPrimeTimeout)
      Sets the maximum time allowed for each channel-primer attempt, including the synchronous call to the primer. Zero uses the 10-second default.

    • setChannelPrimeMaxAttempts

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setChannelPrimeMaxAttempts(int channelPrimeMaxAttempts)
      Sets the maximum number of attempts to prime one scaled-up channel. Zero uses the default of 3. Retry backoff is exponential from 100 ms and capped at 5 s.

    • setConcurrentStreamsLowWatermark

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setConcurrentStreamsLowWatermark(int concurrentStreamsLowWatermark)
      Sets the concurrent streams low watermark. If every channel in the pool has at least this amount of concurrent streams then a new channel will be created in the pool unless the pool reached its maximum size.
      Parameters:
      concurrentStreamsLowWatermark - number of streams every channel must reach before adding a new channel to the pool.

    • setUseRoundRobinOnBind

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setUseRoundRobinOnBind(boolean enabled)
      Enables/disables using round-robin channel selection for affinity binding calls.
      Parameters:
      enabled - If true, use round-robin channel selection for affinity binding calls.

    • setAffinityKeyLifetime

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setAffinityKeyLifetime(Duration affinityKeyLifetime)
      How long to keep an affinity key after its last use. Zero value means keeping keys forever.
      Parameters:
      affinityKeyLifetime - time since last use of a key to include the key in a cleanup.

    • setCleanupInterval

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setCleanupInterval(Duration cleanupInterval)
      How frequently affinity key cleanup process should run. Zero value disables cleanup process. If affinityKeyLifetime is not zero, this defaults to affinityKeyLifetime / 10.
      Parameters:
      cleanupInterval - frequency of affinity key cleanup.

    • setChannelPickStrategy

      public GcpManagedChannelOptions.GcpChannelPoolOptions.Builder setChannelPickStrategy(GcpManagedChannelOptions.ChannelPickStrategy strategy)
      Sets the strategy for picking the least busy channel from the pool.

      Defaults to GcpManagedChannelOptions.ChannelPickStrategy.POWER_OF_TWO which avoids the thundering herd problem by sampling two channels with replacement and picking the less busy one. The first sample wins ties, with no channel-warmth preference. Inactive samples are retried.

      Use GcpManagedChannelOptions.ChannelPickStrategy.LINEAR_SCAN to restore the legacy behavior of scanning all channels and always picking the one with the lowest picker load.

      Parameters:
      strategy - the channel pick strategy to use.