--- a/xml/en/docs/ngx_core_module.xml
+++ b/xml/en/docs/ngx_core_module.xml
@@ -397,6 +397,39 @@ Defines the name of the hardware SSL acc
 </directive>
 
 
+<directive name="thread_pool">
+<syntax>
+    <value>name</value>
+    <literal>threads</literal>=<value>number</value>
+    [<literal>max_queue</literal>=<value>number</value>]</syntax>
+<default>default threads=32 max_queue=65536</default>
+<context>main</context>
+<appeared-in>1.7.11</appeared-in>
+
+<para>
+Defines named thread pools
+used for multi-threaded reading and sending of files
+<link doc="http/ngx_http_core_module.xml" id="aio">without blocking</link>
+worker processes.
+</para>
+
+<para>
+The <literal>threads</literal> parameter
+defines the number of threads in the pool.
+</para>
+
+<para>
+In the event that all threads in the pool are busy,
+a new task will wait in the queue.
+The <literal>max_queue</literal> parameter limits the number
+of tasks allowed to be waiting in the queue.
+By default, up to 65536 tasks can wait in the queue.
+When the queue overflows, the task is completed with an error.
+</para>
+
+</directive>
+
+
 <directive name="timer_resolution">
 <syntax><value>interval</value></syntax>
 <default/>