==NOTICE=
This patch may be just usable under the version of Nginx_1.0.5. It just adds the
support for the upstream keepalive connection and it isn't a completed HTTP/1.1
patch.

The core Nginx developer Maxim Dounin has released a completed patch for Nginx
HTTP/1.1 proxying (http://forum.nginx.org/read.php?2,213207). It will be merged
into the 1.1.x branch of Nginx(http://mailman.nginx.org/pipermail/nginx-devel/2011-July/001083.html).

This patch has merged into the Nginx-1.1.4 branch. 

I suggest you should use this patch. Good luck.

==INSTALLATION==
    
cd nginx-1.0.5
patch -p1 < /path/to/this/directory/upstream_keepalive_1.0.5.patch

#add the module
./configure --add-module=/path/to/this/directory


==EXAMPLE==

upstream backends {
    server 10.0.0.1;
    server 10.0.0.2;

    keepalive 128;
}

Append the header of "Connection: keep-alive" with the proxy packet:

location /foo {
    proxy_set_header Connection "keep-alive";
    proxy_pass http://backends;
}

The ngx_http_upstream_keepalive_module's document is here:
https://github.com/yaoweibin/nginx_upstream_keepalive_patch/raw/master/ngx_http_upstream_keepalive/README

Notice that, this module keep connections in a pool. All the backend connections
will not be timeout or closed actively by this module, unless the backend 
server close the connection.  

==COPYRIGHT & LICENSE==

This original patch and ngx_http_upstream_keepalive_module is written by 
Maxim Dounin and published under the BSD license.

This patch is also published under the BSD license.

Copyright (C) 2011 by Weibin Yao <yaoweibin@gmail.com>.

Thanks to Simpli.fi to sponsor this patch.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

*   Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.

*   Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.

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IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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