Set GOMAXPROCS explicitly

Signed-off-by: Davanum Srinivas <davanum@gmail.com>

hack/lib/golang.sh

@@ -554,6 +554,19 @@ kube::golang::setup_env() {
 
   # This seems to matter to some tools
   export GO15VENDOREXPERIMENT=1
+
+  # GOMAXPROCS by default does not reflect the number of cpu(s) available
+  # when running in a container, please see https://github.com/golang/go/issues/33803
+  if ! command -v ncpu >/dev/null 2>&1; then
+    # shellcheck disable=SC2164
+    pushd "${KUBE_ROOT}/hack/tools" >/dev/null
+    GO111MODULE=on go install ./ncpu
+    # shellcheck disable=SC2164
+    popd >/dev/null
+  fi
+
+  GOMAXPROCS=${GOMAXPROCS:-$(ncpu)}
+  kube::log::status "Setting GOMAXPROCS: ${GOMAXPROCS}"
 }
 
 # This will take binaries from $GOPATH/bin and copy them to the appropriate