httpd-cvs mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From elu...@apache.org
Subject svn commit: r1772400 - /httpd/httpd/trunk/docs/manual/mod/event.html.en
Date Fri, 02 Dec 2016 19:21:52 GMT
Author: elukey
Date: Fri Dec  2 19:21:51 2016
New Revision: 1772400

URL: http://svn.apache.org/viewvc?rev=1772400&view=rev
Log:
mpm-event's doc rebuild

Modified:
    httpd/httpd/trunk/docs/manual/mod/event.html.en

Modified: httpd/httpd/trunk/docs/manual/mod/event.html.en
URL: http://svn.apache.org/viewvc/httpd/httpd/trunk/docs/manual/mod/event.html.en?rev=1772400&r1=1772399&r2=1772400&view=diff
==============================================================================
--- httpd/httpd/trunk/docs/manual/mod/event.html.en (original)
+++ httpd/httpd/trunk/docs/manual/mod/event.html.en Fri Dec  2 19:21:51 2016
@@ -150,7 +150,7 @@ of the <code class="directive">AsyncRequ
         and also the number of allowed processes
         (<code class="directive"><a href="../mod/mpm_common.html#maxrequestworkers">MaxRequestWorkers</a></code>

         / <code class="directive"><a href="../mod/mpm_common.html#threadsperchild">ThreadsPerChild</a></code>),
meanwhile
-        the Scoreboad is a representation of all the running processes and
+        the Scoreboard is a representation of all the running processes and
         the status of their worker threads. If the scoreboard is full (so all the
         threads have a state that is not idle) but the number of active requests
         served is not <code class="directive"><a href="../mod/mpm_common.html#maxrequestworkers">MaxRequestWorkers</a></code>,
@@ -158,17 +158,24 @@ of the <code class="directive">AsyncRequ
         but that are queued instead (up to the limit imposed by
         <code class="directive"><a href="../mod/mpm_common.html#listenbacklog">ListenBacklog</a></code>).
Most of the times
         the threads are stuck in the Graceful state, namely they are waiting to
-        finish their work with a TCP connection to terminate and free a
+        finish their work with a TCP connection to safely terminate and free up a
         scoreboard slot (for example handling long running requests, slow clients
-        or a connection with keep-alive enabled). Two scenarios are very common:</p>
+        or connections with keep-alive enabled). Two scenarios are very common:</p>
         <ul>
-            <li>Httpd graceful restart.</li>
+            <li>During a <a href="../stopping.html#graceful">graceful restart</a>.
+            The parent process signals all its children to complete
+            their work and terminate, while it reloads the config and forks new
+            processes. If the old children keep running for a while before stopping,
+            the scoreboard will be partially occupied until their slots are freed.
+            </li>
             <li>When the server load goes down in a way that causes httpd to
             stop some processes (for example due to
             <code class="directive"><a href="../mod/mpm_common.html#maxsparethreads">MaxSpareThreads</a></code>).
             This is particularly problematic because when the load increases again,
-            httpd will try to start more processes.
-            If the pattern repeats, the number of processes can rise quite a bit.
+            httpd will try to start new processes.
+            If the pattern repeats, the number of processes can rise quite a bit,
+            ending up in a mixture of old processes trying to stop and new ones
+            trying to do some work.
             </li>
         </ul>
         <p>From 2.4.24 onward, mpm-event is smarter and it is able to handle



Mime
View raw message