Commit 63f0e298 authored by Marc Slemko's avatar Marc Slemko
Browse files

Add some more detailed information about ListenBacklog and MaxClients, 

plus a few misc cleanups.

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git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@82008 13f79535-47bb-0310-9956-ffa450edef68
parent c8ee1509

docs/manual/mod/core.html

+22 −9
Changes for docs/manual/mod/core.html: 22 added lines, 9 removed lines.
Original line number Diff line number Diff line
@@ -1135,7 +1135,7 @@ only processed if the parameter named <EM>parameter-name</EM> is defined. 
The second format reverses the test, and only processes the directives if

<EM>parameter-name</EM> is <STRONG>not</STRONG> defined.



<P>The <EM>paramater-name</EM> argument is a define as given on the

<P>The <EM>parameter-name</EM> argument is a define as given on the

<CODE>httpd</CODE> command line via <CODE>-D</CODE><EM>parameter-</EM>, at the

time the server was started.
@@ -1613,12 +1613,18 @@ interfaces and port numbers, use 
 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> ListenBacklog is only available in Apache

versions after 1.2.0.<P>

versions after 1.2.0.



The maximum length of the queue of pending connections.  Generally no

<P>The maximum length of the queue of pending connections.  Generally no

tuning is needed or desired, however on some systems it is desirable

to increase this when under a TCP SYN flood attack.  See

the backlog parameter to the <CODE>listen(2)</CODE> system call.</P><HR>

the backlog parameter to the <CODE>listen(2)</CODE> system call.



<P>This will often be limited to a smaller number by the operating

system.  This varies from OS to OS.  Also note that many OSes do not

use exactly what is specified as the backlog, but use a number based on

(but normally larger than) what is set.

<HR>



<H2><A NAME="location">&lt;Location&gt; directive</A></H2>
@@ -1878,10 +1884,17 @@ Using a level of at least <CODE>crit</CODE> is recommended. 
 REL="Help"

><STRONG>Status:</STRONG></A> core<P>



The MaxClients directive sets the limit on the number of simultaneous

<P>The MaxClients directive sets the limit on the number of simultaneous

requests that can be supported; not more than this number of child server

processes will be created.  To configure more than 256 clients, you must

edit the HARD_SERVER_LIMIT entry in httpd.h and recompile.<P><HR>

edit the HARD_SERVER_LIMIT entry in httpd.h and recompile.



<P>Any connection attempts over the MaxClients limit will normally

be queued, up to a number based on the <A HREF="#listenbacklog">

ListenBacklog</A> directive.  Once a child process is freed at the

end of a different request, the connection will then be serviced.



<HR>



<H2><A NAME="maxkeepaliverequests">MaxKeepAliveRequests directive</A></H2>

<A
@@ -2928,7 +2941,7 @@ See also <A HREF="#minspareservers">MinSpareServers</A> and 
 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> core (Windows)<BR>

<STRONG>Compatbility:</STRONG> Available only with Apache 1.3 and later

<STRONG>Compatibility:</STRONG> Available only with Apache 1.3 and later

with Windows



<P>This directive tells the server how many threads it should use. This
@@ -3072,8 +3085,8 @@ meant for httpd requests. It is recommended that you set up a new user and 
group specifically for running the server. Some admins use user

<CODE>nobody</CODE>, but this is not always possible or desirable.

For example mod_proxy's cache, when enabled, must be accessible to this user

(see the <A href="mod_proxy.html#cacheroot"><CODE>CacheRoot</CODE></a> 

directive</a>).<P>

(see the <A href="mod_proxy.html#cacheroot"><CODE>CacheRoot</CODE>

directive</A>).<P>



Notes: If you start the server as a non-root user, it will fail to change

to the lesser privileged user, and will instead continue to run as