*_cache_revalidate directives

[Alt]

Hello,

>From the documentation, I don't understand how the fastcgi_cache_revalidate
(or scgi_cache_revalidate or proxy_cache_revalidate or
uwsgi_cache_revalidate) works.
Please, can someone explain what nginx does when cache is enabled and the
revalidate directive is set to "on"?

Best Regards

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,260148,260148#msg-260148