What could prevent gzip_comp_level from chaning?

Hi all,

According to yslow I seem to get the exact same size gzipped version of
the page no matter what I set gzip_comp_level to. Does anyone know why
that might be the case? This is for the page html (generated by
mongrel) so not static content and I’ve checked a couple of different
pages (some several hundred kb in size where I’d expect to see some
difference) restarting nginx each time I changed the config file. I’ve
included the output of nginx -V and the relevant portion of the nginx
config below.


http {

gzip settings - compression saves bandwidth, 256 * 16 => 4mb max


file size (actual max? seem like it streams through and still


even when doesn’t fit as we used to have this much smaller and it


seem to prevent large pages from getting gzipped…)

gzip on;
gzip_min_length 512;
gzip_buffers 256 16k;

FIXME - good compression level? Tradeoff of servertime/serverload



gzip_comp_level 6;
gzip_proxied any;

note that text/html is always gzipped

gzip_types text/plain text/css application/x-javascript
application/xml+rss text/javascript;

with gzip_static on we can pre-compress our static files rather then

recompressing them over and over again on the fly. All we need is


versions of the files in the same locations with identical

gzip_static on;

FIXME - I’m not sure if we should be setting these or not, for now


defaults are reasonable


Response Buffers - buffers requests from the servers to the client

(freeing up the servers from slow clients). On by default but we

reiterate for clarity.

1024 * 16kb => 16mb max memory bufferable request response size.

proxy_buffering on;
proxy_buffers 1024 16k;

initial buffer size

proxy_buffer_size 8k;

disable buffering to disk if response size exceeds proxy_buffers (so


stream from mongrel if memory size is exceeded), if non-zero this is


max size that will be buffered to disk

FIXME - we’ve made the memory cache size gigantic to compensate

(since we

do still rarely serve very, very large pages).

proxy_max_temp_file_size 0;

$ nginx -V
nginx version: nginx/0.7.65
built by gcc 4.2.4 (Ubuntu 4.2.4-1ubuntu4)
TLS SNI support disabled
configure arguments: --prefix=/usr/local/pkg/nginx-0.7.65
–with-md5=/usr/lib --http-log-path=/var/log/nginx/nginx_access.log
–error-log-path=/var/log/nginx/nginx_error.log --with-http_ssl_module
–with-http_flv_module --with-http_sub_module --user=www-data
–group=www-data --pid-path=/var/run/nginx.pid
–conf-path=/etc/nginx/nginx.conf --with-http_gzip_static_module

$ sudo nginx -t
the configuration file /etc/nginx/nginx.conf syntax is ok
configuration file /etc/nginx/nginx.conf test is successful