diff --git a/doc/demo.sh b/doc/demo.sh
index 13aa479..83798ff 100755
--- a/doc/demo.sh
+++ b/doc/demo.sh
@@ -111,6 +111,8 @@ sysctl -w net.core.rmem_max=16777216
 sysctl -w net.core.wmem_max=16777216
 sysctl -w net.core.rmem_default=16777216
 sysctl -w net.core.wmem_default=16777216
+sysctl -w net.ipv4.tcp_rmem="16777216 131072 16777216"
+sysctl -w net.ipv4.tcp_wmem="16777216 131072 16777216"
 
 echo
 echo "Namespace ${ns} set up, addresses:"