Alternative Web Servers

Two alternative web servers are currently available on DreamHost PS other than Apache: Lighttpd and Nginx. This article lists some of the ways in which these web servers differ from Apache.

Feature comparison

Feature	Apache	Lighttpd	nginx	Notes
Speed	Slow	Fast	Fast	Lighttpd and nginx are significantly faster than Apache, with nginx serving small files up to eight times faster!
Memory Use	Heavier	Lighter	Lighter	Lighttpd and nginx often use much less memory than Apache.
HTML, etc.	Yes	Yes	Yes	Lighttpd and nginx excel at serving static content such as HTML.
CGI	Yes	No	No	FastCGI scripts can be used on Lighttpd and nginx, but only with some custom configuration.
PHP	Yes	Yes	Yes	With some caveats. See #PHP (below) for details.
Passenger	Yes	No	Yes	nginx runs Passenger-based sites quite well — it's an ideal choice for a Rails or Django site.
.htaccess	Yes	No	No	However, some customization is still possible - see Lighttpd and nginx for details. mod_rewrite rules will need to be (manually) converted to function.
Subversion repositories	Yes	No	No	Repositories will remain intact under other web servers, but cannot be accessed over HTTP(S).
WebDAV	Yes	No	No

PHP

PHP scripts will run on all three web servers - but only as FastCGI. (CGI and mod_php are not available on other web servers.) However, some environment variables may be set slightly differently depending on the web server, causing some scripts to behave incorrectly.

Additionally, Lighttpd and Nginx start all PHP worker processes at startup — one for each user on the PS with PHP scripts. If you have many users on your PS, this may consume a significant quantity of RAM.

If you do not need PHP for any of the web sites on your PS, you may disable it at Configure Server. This will save you a significant chunk of memory (20–30 MB per user).