Allow setting --concurrent-service-syncs for kube-controller-manager in GCE startup scripts

cluster/gce/config-default.sh

@@ -338,3 +338,7 @@ fi
 
 # Optional: enable certificate rotation of the kubelet certificates.
 ROTATE_CERTIFICATES="${ROTATE_CERTIFICATES:-}"
+
+# The number of services that are allowed to sync concurrently. Will be passed
+# into kube-controller-manager via `--concurrent-service-syncs`
+CONCURRENT_SERVICE_SYNCS="${CONCURRENT_SERVICE_SYNCS:-}"

cluster/gce/config-test.sh

@@ -389,3 +389,7 @@ fi
 
 # Optional: enable certificate rotation of the kubelet certificates.
 ROTATE_CERTIFICATES="${ROTATE_CERTIFICATES:-}"
+
+# The number of services that are allowed to sync concurrently. Will be passed
+# into kube-controller-manager via `--concurrent-service-syncs`
+CONCURRENT_SERVICE_SYNCS="${CONCURRENT_SERVICE_SYNCS:-}"

cluster/gce/container-linux/configure-helper.sh

@@ -1103,6 +1103,9 @@ function start-kube-controller-manager {
   if [[ -n "${SERVICE_CLUSTER_IP_RANGE:-}" ]]; then
     params+=" --service-cluster-ip-range=${SERVICE_CLUSTER_IP_RANGE}"
   fi
+  if [[ -n "${CONCURRENT_SERVICE_SYNCS:-}" ]]; then
+    params+=" --concurrent-service-syncs=${CONCURRENT_SERVICE_SYNCS}"
+  fi
   if [[ "${NETWORK_PROVIDER:-}" == "kubenet" ]]; then
     params+=" --allocate-node-cidrs=true"
   elif [[ -n "${ALLOCATE_NODE_CIDRS:-}" ]]; then

cluster/gce/gci/configure-helper.sh

@@ -1581,6 +1581,9 @@ function start-kube-controller-manager {
   if [[ -n "${SERVICE_CLUSTER_IP_RANGE:-}" ]]; then
     params+=" --service-cluster-ip-range=${SERVICE_CLUSTER_IP_RANGE}"
   fi
+  if [[ -n "${CONCURRENT_SERVICE_SYNCS:-}" ]]; then
+    params+=" --concurrent-service-syncs=${CONCURRENT_SERVICE_SYNCS}"
+  fi
   if [[ "${NETWORK_PROVIDER:-}" == "kubenet" ]]; then
     params+=" --allocate-node-cidrs=true"
   elif [[ -n "${ALLOCATE_NODE_CIDRS:-}" ]]; then

cluster/kubemark/gce/config-default.sh

@@ -116,3 +116,7 @@ ENABLE_POD_PRIORITY="${ENABLE_POD_PRIORITY:-}"
 if [[ "${ENABLE_POD_PRIORITY}" == "true" ]]; then
     FEATURE_GATES="${FEATURE_GATES},PodPriority=true"
 fi
+
+# The number of services that are allowed to sync concurrently. Will be passed
+# into kube-controller-manager via `--concurrent-service-syncs`
+CONCURRENT_SERVICE_SYNCS="${CONCURRENT_SERVICE_SYNCS:-}"