Interface LoadReportingServiceGrpc.AsyncService

All Known Implementing Classes:
LoadReportingServiceGrpc.LoadReportingServiceImplBase
Enclosing class:
LoadReportingServiceGrpc

public static interface LoadReportingServiceGrpc.AsyncService
  • Method Summary

    Modifier and Type
    Method
    Description
    default io.grpc.stub.StreamObserver<LoadStatsRequest>
    streamLoadStats(io.grpc.stub.StreamObserver<LoadStatsResponse> responseObserver)
    Advanced API to allow for multi-dimensional load balancing by remote server.
  • Method Details

    • streamLoadStats

      default io.grpc.stub.StreamObserver<LoadStatsRequest> streamLoadStats(io.grpc.stub.StreamObserver<LoadStatsResponse> responseObserver)
       Advanced API to allow for multi-dimensional load balancing by remote
       server. For receiving LB assignments, the steps are:
       1, The management server is configured with per cluster/zone/load metric
          capacity configuration. The capacity configuration definition is
          outside of the scope of this document.
       2. Envoy issues a standard {Stream,Fetch}Endpoints request for the clusters
          to balance.
       Independently, Envoy will initiate a StreamLoadStats bidi stream with a
       management server:
       1. Once a connection establishes, the management server publishes a
          LoadStatsResponse for all clusters it is interested in learning load
          stats about.
       2. For each cluster, Envoy load balances incoming traffic to upstream hosts
          based on per-zone weights and/or per-instance weights (if specified)
          based on intra-zone LbPolicy. This information comes from the above
          {Stream,Fetch}Endpoints.
       3. When upstream hosts reply, they optionally add header <define header
          name> with ASCII representation of EndpointLoadMetricStats.
       4. Envoy aggregates load reports over the period of time given to it in
          LoadStatsResponse.load_reporting_interval. This includes aggregation
          stats Envoy maintains by itself (total_requests, rpc_errors etc.) as
          well as load metrics from upstream hosts.
       5. When the timer of load_reporting_interval expires, Envoy sends new
          LoadStatsRequest filled with load reports for each cluster.
       6. The management server uses the load reports from all reported Envoys
          from around the world, computes global assignment and prepares traffic
          assignment destined for each zone Envoys are located in. Goto 2.