diff --git a/config.yaml b/config.yaml
index 132c8f4..d087510 100644
--- a/config.yaml
+++ b/config.yaml
@@ -157,10 +157,12 @@ options:
       your network interface.
   sysctl:
     type: string
-    default: ''
+    default: '{ kernel.pid_max : 2097152 }'
     description: |
       YAML-formatted associative array of sysctl key/value pairs to be set
-      persistently e.g. '{ kernel.pid_max : 4194303 }'.
+      persistently. As a default we set pid_max to a high value to avoid
+      problems with large numbers (>20) of OSDs recovering. very large clusters
+      should set this value even higher (max 4194303).
   nagios_context:
     default: "juju"
     description: |