--- a/xml/en/docs/http/ngx_http_proxy_module.xml
+++ b/xml/en/docs/http/ngx_http_proxy_module.xml
@@ -248,7 +248,10 @@ will be cached.
     [<literal>levels</literal>=<value>levels</value>]
     <literal>keys_zone</literal>=<value>name</value>:<value>size</value>
     [<literal>inactive</literal>=<value>time</value>]
-    [<literal>max_size</literal>=<value>size</value>]</syntax>
+    [<literal>max_size</literal>=<value>size</value>]
+    [<literal>loader_files</literal>=<value>number</value>]
+    [<literal>loader_sleep</literal>=<value>time</value>]
+    [<literal>loader_threshold</literal>=<value>time</value>]</syntax>
 <default/>
 <context>http</context>
 
@@ -295,6 +298,19 @@ by the <literal>max_size</literal> param
 when this size is exceeded it removes the least recently used data.
 </para>
 
+<para>
+A minute after the start the special process “cache loader” is activated
+that loads information about previously cached data stored on file system
+into a cache zone.
+A load is done in iterations.
+During one iteration no more than <literal>loader_files</literal> items
+are loaded (by default, 100).
+Besides, the duration of one iteration is limited by the
+<literal>loader_threshold</literal> parameter (by default, 200 milliseconds).
+A pause is made between iterations, configured by the
+<literal>loader_sleep</literal> parameter (by default, 50 milliseconds).
+</para>
+
 </directive>