Slow Operations Logging

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    Tracing information on slow operations can be found in the logs as threshold logging, orphan logging, and other span metrics. Change the settings to alter how much information you collect

    To improve debuggability certain metrics are automatically measured and logged. These include slow queries, responses taking beyond a certain threshold, and orphanned responses.

    Threshold Logging Reporting

    Threshold logging is the recording of slow operations — useful for diagnosing when and where problems occur in a distributed environment.

    Output Format

    You should expect to see output in JSON format in the logs for the services encountering problems:

    {
      "<service-a>": {
        "total_count": 1234,
        "top_requests": [{<entry>}, {<entry>},...]
      },
      "<service-b>": {
        "total_count": 1234,
        "top_requests": [{<entry>}, {<entry>},...]
      },
    }

    The total_count represents the total amount of over-threshold recorded items in each interval per service. The number of entries in “top_requests” is configured by the SampleSize. The service placeholder is replaced with each service — “kv”, “query”, etc. Each entry looks like this, with all fields populated:

    {
      "total_duration_us": 1200,
      "encode_duration_us": 100,
      "last_dispatch_duration_us": 40,
      "total_dispatch_duration_us": 40,
      "last_server_duration_us": 2,
      "operation_name": "upsert",
      "last_local_id": "66388CF5BFCF7522/18CC8791579B567C",
      "operation_id": "0x23",
      "last_local_socket": "10.211.55.3:52450",
      "last_remote_socket": "10.112.180.101:11210"
    }

    If a field is not present (because for example dispatch did not happen), it will not be included.

    Configuring Threshold Logging

    Configuration of the ThresholdLoggingTracer is done on the tracer itself, at creation time. If no tracer is configured using ClusterOptions.Tracer then the default ThresholdLoggingTracer will be used.

    	tracerOpts := &gocb.ThresholdLoggingOptions{
    		Interval:   10 * time.Second,
    		SampleSize: 10,
    	}
    	tracer := gocb.NewThresholdLoggingTracer(tracerOpts)
    
    	opts := gocb.ClusterOptions{
    		Authenticator: gocb.PasswordAuthenticator{
    			Username: "Administrator",
    			Password: "password",
    		},
    		Tracer: tracer,
    	}

    The following properties can be configured:

    Property Default Description

    Interval

    10 seconds

    The interval where found slow operations are emitted.

    SampleSize

    10

    The number of samples to store per service.

    KVThreshold

    500 milliseconds

    The threshold over which the request is taken into account for the KV service.

    ViewsThreshold

    1 second

    The threshold over which the request is taken into account for the views service.

    QueryThreshold

    1 second

    The threshold over which the request is taken into account for the query service.

    SearchThreshold

    1 second

    The threshold over which the request is taken into account for the search service.

    AnalyticsThreshold

    1 second

    The threshold over which the request is taken into account for the analytics service.

    ManagementThreshold

    1 second

    The threshold over which the request is taken into account for the management service.