Running Django with FastCGI or with mod_python

Question

which would you recommend? which is faster, reliable? apache mod_python or nginx/lighttpd FastCGI?

Answer 1

I've done both, and Apache/mod_python tended to be easier to work with and more stable. But these days I've jumped over to Apache/mod_wsgi, which is everything I've ever wanted and more:

• Easy management of daemon processes.
• As a result, much better process isolation (running multiple sites in the same Apache config with mod_python almost always ends in trouble -- environment variables and C extensions leak across sites when you do that).
• Easy code reloads (set it up right and you can just touch the .wsgi file to reload instead of restarting Apache).
• More predictable resource usage. With mod_python, a given Apache child process' memory use can jump around a lot. With mod_wsgi it's pretty stable: once everything's loaded, you know that's how much memory it'll use.

Answer 2

lighttpd with FastCGI will be nominally faster, but really the time it takes to run your python code and any database hits it does is going to absolutely dwarf any performance benefit you get between web servers.

mod_python and apache will give you a bit more flexibility feature-wise if you want to write code outside of django that does stuff like digest auth, or any fancy HTTP header getting/setting. Perhaps you want to use other builtin features of apache such as mod_rewrite.

If memory is a concern, staying away form apache/mod_python will help a lot. Apache tends to use a lot of RAM, and the mod_python code that glues into all of the apache functionality occupies a lot of memory-space as well. Not to mention the multiprocess nature of apache tends to eat up more RAM, as each process grows to the size of it's most intensive request.