diff --git a/docs/static/persistent-queues.asciidoc b/docs/static/persistent-queues.asciidoc
index b2b31bef6..6890fc045 100644
--- a/docs/static/persistent-queues.asciidoc
+++ b/docs/static/persistent-queues.asciidoc
@@ -56,6 +56,10 @@ queue will be sized at the value of `queue.max_bytes` specified in
 `logstash.yml`. 
 The default is 1024mb (1gb).
 +
+NOTE: Be sure that your disk has sufficient capacity to handle the cumulative total of `queue.max_bytes` across all persistent queues.
+The total of `queue.max_bytes` for _all_ queues should be
+lower than the capacity of your disk.
++
 TIP: If you are using persistent queues to protect against data loss, but don't
 require much buffering, you can set `queue.max_bytes` to a smaller value.
 A smaller value produces smaller queues and improves queue performance.