* mod/mod_proxy.xml: First Draft trying to explain how to tune pooled connections.

<div class="directive-section"><h2><a name="ProxyPass" id="ProxyPass">ProxyPass</a> <a name="proxypass" id="proxypass">Directive</a></h2>

<table class="directive">

<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maps remote servers into the local server URL-space</td></tr>

<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPass [<var>path</var>] !|<var>url</var></code></td></tr>

<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPass [<var>path</var>] !|<var>url</var> [<var>key=value</var> <var>key=value</var> ...]]</code></td></tr>

<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>

<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>

<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>

      general <code class="directive">ProxyPass</code> directive.</p>

    </div>

    <p>New in Apache 2.1, is the ability to use pooled connections to a 

    backend server. Using the <code>key=value</code> parameters it is possible

    to tune this connection pooling. The default for a <code>Hard Maximum</code>

    for the number of connections is the number of threads per process in the 

    active MPM. In the Prefork MPM, this is always 1, while with the Worker MPM

    it is controlled by the <code class="directive">ThreadsPerChild</code>.</p>

    <p>Setting <code>min</code> will determine how many connections will always 

    be open to the backend server. Upto the Soft Maximum or <code>smax</code> 

    number of connections will be created on demand. Any connections above 

    <code>smax</code> are subject to a time to live or <code>ttl</code>.  Apache

    will never create more than the Hard Maximum or <code>hmax</code> connections

    to the backend server.</p>

    <div class="example"><p><code>

        ProxyPass /example http://backend.example.com min=0 smax=5 hmax=20 ttl=60

    </code></p></div>

    <p>When used inside a <code class="directive"><a href="../mod/core.html#location">&lt;Location&gt;</a></code> section, the first argument is omitted and the local

    directory is obtained from the <code class="directive"><a href="../mod/core.html#location">&lt;Location&gt;</a></code>.</p>

<directivesynopsis>

<name>ProxyPass</name>

<description>Maps remote servers into the local server URL-space</description>

<syntax>ProxyPass [<var>path</var>] !|<var>url</var></syntax>

<syntax>ProxyPass [<var>path</var>] !|<var>url</var> [<var>key=value</var> <var>key=value</var> ...]]</syntax>

<contextlist><context>server config</context><context>virtual host</context>

<context>directory</context>

</contextlist>

      general <directive>ProxyPass</directive> directive.</p>

    </note>

    <p>New in Apache 2.1, is the ability to use pooled connections to a 

    backend server. Using the <code>key=value</code> parameters it is possible

    to tune this connection pooling. The default for a <code>Hard Maximum</code>

    for the number of connections is the number of threads per process in the 

    active MPM. In the Prefork MPM, this is always 1, while with the Worker MPM

    it is controlled by the <directive>ThreadsPerChild</directive>.</p>

    <p>Setting <code>min</code> will determine how many connections will always 

    be open to the backend server. Upto the Soft Maximum or <code>smax</code> 

    number of connections will be created on demand. Any connections above 

    <code>smax</code> are subject to a time to live or <code>ttl</code>.  Apache

    will never create more than the Hard Maximum or <code>hmax</code> connections

    to the backend server.</p>

    <example>

        ProxyPass /example http://backend.example.com min=0 smax=5 hmax=20 ttl=60

    </example>

    <!-- Still to be documented:

             retry acquire timeout 

             iobuffersize receivebuffersize 

             keepalive route redirect 

         See modules/proxy/mod_proxy.c set_worker_param() for details.  -->

    <p>When used inside a <directive type="section" module="core"

    >Location</directive> section, the first argument is omitted and the local

    directory is obtained from the <directive type="section" module="core"