diff --git a/reference/filesystem/functions/readfile.xml b/reference/filesystem/functions/readfile.xml
index c6779a9027..e4bd76ae78 100644
--- a/reference/filesystem/functions/readfile.xml
+++ b/reference/filesystem/functions/readfile.xml
@@ -101,10 +101,19 @@ if (file_exists($file)) {
  </refsect1>
 
  <refsect1 role="notes">
+  <note>
+   <para>
+    <function>readfile</function> will not present any memory issues, 
+    even when sending large files, on its own. If you encounter an 
+    out of memory error ensure that output buffering is off with 
+    <function>ob_get_level</function>.
+   </para>
+  </note>
   &reftitle.notes;
 
   &tip.fopen-wrapper;
   &note.context-support;
+
  </refsect1>
  
  <refsect1 role="seealso">