Replace AlwaysSample with ProbabilitySampler in router (#1348)

charts/fission-core/templates/router.yaml

@@ -54,7 +54,7 @@ spec:
           - name: ROUTER_SVC_ADDRESS_UPDATE_TIMEOUT
             value: {{ .Values.router.svcAddressUpdateTimeout | default "30s" | quote }}
           - name: TRACING_SAMPLING_RATE
-            value: {{ .Values.traceSamplingRate | default "0.5" | quote }}
+            value: {{ .Values.router.traceSamplingRate | default "0.5" | quote }}
           - name: USE_ENCODED_PATH
             value: {{ .Values.router.useEncodedPath | default false | quote }}
           - name: DEBUG_ENV

charts/fission-core/values.yaml

@@ -85,6 +85,9 @@ router:
     ## Max retries times of a failed request
     maxRetries: 10
 
+  ## Sample with a rate per time window (traces/second)
+  traceSamplingRate: 0.5
+
 ## Persist data to a persistent volume.
 persistence:
   ## If true, fission will create/use a Persistent Volume Claim