Package com.linkedin.venice.listener

Class ServerStatsContext

java.lang.Object
com.linkedin.venice.listener.ServerStatsContext
public class ServerStatsContext extends Object
We need to be able to record server side statistics for gRPC requests. The current StatsHandler in the Netty Pipeline maintains instance variables per channel, and guarantees that each request will be handled by the same thread, thus we cannot augment StatsHandler in the same way as other handlers for gRPC requests. We create a new StatsContext for each gRPC request, so we can maintain per request stats which will be aggregated on request completion using references to the proper Metrics Repository in AggServerHttpRequestStats. This class is almost a direct copy of StatsHandler, without Netty Channel Read/Write logic.

  • Field Details

    • UNKNOWN_STORE_NAME

      public static final String UNKNOWN_STORE_NAME
      Sentinel store name used when the actual store name is unknown (e.g., request failed before store resolution). Using a sentinel instead of null ensures both Tehuti and OTel metrics are recorded rather than otel getting silently dropped as otel needs non-null values for all dimensions rather than having a diff metric for such cases.
      See Also:

  • Constructor Details

  • Method Details

    • isNewRequest

      public boolean isNewRequest()

    • resetContext

      public void resetContext()

    • setReadResponseStats

      public void setReadResponseStats(ReadResponseStatsRecorder responseStatsRecorder)

    • setNewRequest

      public void setNewRequest()

    • isMetadataRequest

      public boolean isMetadataRequest()

    • isStatCallBackExecuted

      public boolean isStatCallBackExecuted()

    • setStatCallBackExecuted

      public void setStatCallBackExecuted(boolean statCallbackExecuted)

    • setResponseStatus

      public void setResponseStatus(io.netty.handler.codec.http.HttpResponseStatus status)

    • getStoreName

      public String getStoreName()

    • setStoreName

      public void setStoreName(String name)

    • setMetadataRequest

      public void setMetadataRequest(boolean metadataRequest)

    • setRequestTerminatedEarly

      public void setRequestTerminatedEarly()

    • getResponseStatus

      public io.netty.handler.codec.http.HttpResponseStatus getResponseStatus()

    • setRequestType

      public void setRequestType(RequestType requestType)

    • getRequestType

      public RequestType getRequestType()

    • setRequestKeyCount

      public void setRequestKeyCount(int keyCount)

    • getCurrentStats

      public AggServerHttpRequestStats getCurrentStats()

    • setRequestInfo

      public void setRequestInfo(RouterRequest request)

    • setRequestSize

      public void setRequestSize(int requestSizeInBytes)

    • getRequestStartTimeInNS

      public long getRequestStartTimeInNS()

    • setFlushLatency

      public void setFlushLatency(double latency)

    • setResponseSize

      public void setResponseSize(int size)

    • recordBasicMetrics

      public void recordBasicMetrics(ServerHttpRequestStats serverHttpRequestStats)
      Records request-level and response-level metrics for the current request.

      responseStatus must be non-null when this method is called. Both callers enforce this: StatsHandler.write(io.netty.channel.ChannelHandlerContext, java.lang.Object, io.netty.channel.ChannelPromise) throws VeniceException if responseStatus is null, and GrpcOutboundStatsHandler.processRequest(com.linkedin.venice.listener.grpc.GrpcRequestContext) does the same. The null guard on responseStatus below is purely defensive.

      Parameters:
      serverHttpRequestStats - the per-store stats object; may be null if the store name is unknown, in which case this method is a no-op. This is acceptable because when the store is unknown the request failed before store resolution, so most fields here (keyCount, requestSize, responseStats) won't have meaningful values. The critical error count and latency metrics are still captured by errorRequest(com.linkedin.venice.stats.ServerHttpRequestStats, double), which resolves unknown stores to UNKNOWN_STORE_NAME.

    • successRequest

      public void successRequest(ServerHttpRequestStats stats, double elapsedTime)

    • errorRequest

      public void errorRequest(ServerHttpRequestStats stats, double elapsedTime)
      Records error request metrics. When stats is null (store unknown), resolves a per-store stats object using UNKNOWN_STORE_NAME so that both Tehuti and OTel metrics are recorded rather than OTel getting silently dropped.

      This method does not have to be synchronized since Tehuti Sensor.record() is internally synchronized and OTel SDK recording methods are thread-safe. Please re-consider if new logic is added.

    • getRequestKeyCount

      public int getRequestKeyCount()

    • setMisroutedStoreVersion

      public void setMisroutedStoreVersion(boolean misroutedStoreVersion)