diff --git a/README.md b/README.md
index 1ce0abe..023707c 100644
--- a/README.md
+++ b/README.md
@@ -13,3 +13,7 @@ The haserl version for slim devices without php
 ### Requirements
 * haserl
 * netcat with ipv6 support
+
+## Apache 2 settings
+To avoid OOM Killer it's usefull to reduce the MaxConnectionsPerChild on apache2. On Debian open /etc/apache2/mods-enabled/mpm_prefork.conf and reduce MaxConnectionsPerChild.
+Do not use more then 10 MaxConnectionsPerChild per Gigabyte RAM on your System.
diff --git a/index.php b/index.php
index 6eb81f9..56b242b 100644
--- a/index.php
+++ b/index.php
@@ -23,7 +23,10 @@
 		<?php
 		error_reporting(0);
 		$file="/tmp/babeldump";
-		shell_exec('echo "dump" | nc ::1 33123 -q 1 > '.$file.'');
+
+		if (filemtime($file) < time()-10) {
+			shell_exec('echo "dump" | nc ::1 33123 -q 1 > '.$file.'');
+		}
 
 		$file_handle = fopen($file, 'r');
 		$set=0;