diff --git a/README.md b/README.md
index d2a2e6d..c6da3ce 100644
--- a/README.md
+++ b/README.md
@@ -93,3 +93,5 @@ and pipe its output to the tools:
 bgpq4 -4 -F '%n/%l\n' as-set-name | ./plageq > as-set-name.ipv4.strict.txt
 bgpq4 -6 -F '%n/%l\n' as-set-name | ./plagmax > as-set-name.ipv6.loose.txt
 ```
+
+Tools also output to stderr some statistics of using preallocated memory.