gzip min_length with upstream + ssi

[Igor Sysoev]

On Thu, Sep 17, 2009 at 06:25:42PM +0800, 191919 wrote:

> Just a suggestion: gzip module waits for gzip_min_length bytes, if there is
> enough data, it starts compressing.

There are two modules that send response header only after they
processed whole response. However, now I'm not ready to modify
the gzip filter: there is already undocumented and buggy postpone_gzipping
directive that postpone zlib memory allocation and some time nginx can not
complete response.

> 2009/9/17 Igor Sysoev <is at rambler-co.ru>
> 
> > On Thu, Sep 17, 2009 at 06:11:53PM +0800, 191919 wrote:
> >
> > > Will nginx support using ssi + gzip?
> >
> > nginx supports ssi+gzip. However, gzip_min_length does not work in this
> > case.
> >
> > > 2009/9/17 Igor Sysoev <is at rambler-co.ru>
> > >
> > > > On Thu, Sep 17, 2009 at 05:51:33PM +0800, 191919 wrote:
> > > >
> > > > > Hi there,
> > > > >
> > > > > I encountered a problem when using gzip_min_length with upstream +
> > ssi:
> > > > >
> > > > > ssi on;
> > > > > gzip_min_length 1024;
> > > > > upstream fastcgi_backends
> > > > > {
> > > > >   server unix:/tmp/nx-fastcgi.sock.00;
> > > > > }
> > > > >
> > > > > I wrote a PHP script as:
> > > > >
> > > > > <?
> > > > > header('Content-Length: 3');
> > > > > echo '123';
> > > > > ?>
> > > > >
> > > > > and requested as:
> > > > >
> > > > > GET /2.php HTTP/1.0
> > > > > Accept-Encoding: gzip, deflate
> > > > >
> > > > > nginx returned:
> > > > >
> > > > > HTTP/1.1 200 OK
> > > > > Server: nginx/0.8.15
> > > > > Date: Thu, 17 Sep 2009 09:39:57 GMT
> > > > > Content-Type: text/html
> > > > > Connection: close
> > > > > X-Powered-By: PHP/5.2.8
> > > > > Vary: Accept-Encoding
> > > > > Content-Encoding: gzip
> > > > >
> > > > > 3426???
> > > > >
> > > > > As you see, the content is compressed despite of gzip_min_length =
> > 1024.
> > > > >
> > > > > When I turned off ssi (ssi off;), gzip_min_length works:
> > > > >
> > > > > HTTP/1.1 200 OK
> > > > > Server: nginx/0.8.15
> > > > > Date: Thu, 17 Sep 2009 09:48:11 GMT
> > > > > Content-Type: text/html
> > > > > Connection: close
> > > > > X-Powered-By: PHP/5.2.8
> > > > > Content-Length: 3
> > > > > Vary: Accept-Encoding
> > > > >
> > > > > 123
> > > > >
> > > > > (Commenting out "ngx_http_clear_content_length(r);" in
> > > > > ngx_http_ssi_filter_module.c also works, I didn't test whether ssi
> > still
> > > > > worked.)
> > > >
> > > > SSI deletes "Content-Length" so gzip module does not know about it.
> > > >
> > > >
> > > > --
> > > > Igor Sysoev
> > > > http://sysoev.ru/en/
> > > >
> > > >
> >
> > --
> > Igor Sysoev
> > http://sysoev.ru/en/
> >
> >

-- 
Igor Sysoev
http://sysoev.ru/en/