Try to document the current behavior of MPM event with filters like mod_ssl,

mod_deflate, or mod_include

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1514214 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/docs/manual/mod/event.xml b/docs/manual/mod/event.xml
index 7031cfb37aee969badc2bcc66283fb60b3cc06c0..764608c164a3918d3914e3c24e5507b08932c7b7 100644 (file)
--- a/docs/manual/mod/event.xml
+++ b/docs/manual/mod/event.xml
@@ -66,6 +66,14 @@ of consuming threads only for connections with active processing</description>
     <module>worker</module> MPM and reserve one worker thread per connection.
     All modules shipped with the server are compatible with the event MPM.</p>
 
+    <p>A similar restriction is currently present for requests involving an
+    output filter that needs to read and/or modify the whole response body,
+    like for example mod_ssl, mod_deflate, or mod_include. If the
+    connection to the client blocks while the filter is processing the
+    data, and the amount of data produced by the filter is too big to be
+    buffered in memory, the thread used for the request is not freed while
+    httpd waits until the pending data is sent to the client.</p>
+
     <p>The MPM assumes that the underlying <code>apr_pollset</code>
     implementation is reasonably threadsafe. This enables the MPM to
     avoid excessive high level locking, or having to wake up the listener