Apache + mod_wsgi / Lighttpd + wsgi - am I going to see differences in performance?
That you have mentioned gevent is important. Does that mean you are specifically trying to implement a long polling application? If you are and that functionality is the bulk of the application, then you will need to put your gevent server behind a front end web server that is implemented using async techniques rather that processes/threading model. Lighttd is an async server and fits that bill whereas Apache isn't. So use of Apache isn't good as front end proxy for long polling application. If that is the criteria though, would actually suggest you use nginx rather than Lighttpd.
Now if you are not doing long polling or anything else that needs high concurrency for long running requests, then you aren't necessarily going to gain too much by using gevent, especially if intention is to use a WSGI layer on top. For WSGI applications, ultimately the performance difference between different servers is minimal because your application is unlikely to be a hello world program that the benchmarks all use. The real bottlenecks are not the server but your application code, database, external callouts, lack of caching etc etc. In light of that, you should just use whatever WSGI hosting mechanism you find easier to use initially and when you properly work out what the hosting requirements are for your application, based on having an actual real application to test, then you can switch to something more appropriate if necessary.
In summary, you are just wasting your time trying to prematurely optimize by trying to find what may be the theoretically best server when in practice your application is what you should be concentrating on initially. After that, you also should be looking at application monitoring tools, because without monitoring tools how are you even going to determine if one hosting solution is better than another.
I'm a newbie to developing with Python and I'm piecing together the information I need to make intelligent choices in two other open questions. (This isn't a duplicate.)
I'm not developing using a framework but building a web app from scratch using the gevent library. As far as front-end web servers go, it seems I have three choices: nginx, apache, and lighttpd.
From all accounts that I've read, nginx's mod_wsgi isn't suitable.
That leaves two choices - lighttpd and Apache. Under heavy load, am I going to see major differences in performance and memory consumption characteristics? I'm under the impression Apache tends to be memory hungry even when not using prefork, but I don't know how suitable lighttp is for Python apps.
Are there any caveats or benefits to using lighttpd over apache? I really want to hear all the information you can possibly bore me with!