Make EphemeralRunnerController MaxConcurrentReconciles configurable (#3832)

Co-authored-by: Bassem Dghaidi <568794+Link-@users.noreply.github.com>

charts/gha-runner-scale-set-controller/templates/deployment.yaml

@@ -65,6 +65,9 @@ spec:
         {{- with .Values.flags.watchSingleNamespace }}
         - "--watch-single-namespace={{ . }}"
         {{- end }}
+        {{- with .Values.runnerMaxConcurrentReconciles }}
+        - "--runner-max-concurrent-reconciles={{ . }}"
+        {{- end }}
         {{- with .Values.flags.updateStrategy }}
         - "--update-strategy={{ . }}"
         {{- end }}

charts/gha-runner-scale-set-controller/values.yaml

@@ -106,6 +106,11 @@ flags:
   ## Defaults to watch all namespaces when unset.
   # watchSingleNamespace: ""
 
+  ## The maximum number of concurrent reconciles which can be run by the EphemeralRunner controller.
+  # Increase this value to improve the throughput of the controller.
+  # It may also increase the load on the API server and the external service (e.g. GitHub API).
+  runnerMaxConcurrentReconciles: 2
+
   ## Defines how the controller should handle upgrades while having running jobs.
   ##
   ## The strategies available are: