When using paster web server, does it service requests by creating a new thread?

Question

Does paster create a new thread per request?

Can you set the maximum number of threads for paster to use i.e. a thread pool? How can you if this is possible?

Answer 1

Per the docs, paster supports different server choices, depending on the configuration -- including wsgiutils, "the start of support for twisted.web2 ... patches welcome" (that would be an async server instad), and "SCGI, FastCGI and AJP protocols, for connection an external web server (like Apache) to your application. Both threaded and forking versions are available. This is based on flup."

You can configure maximum number of threads (and/or forked processes) on Apache, for example, and quite independently from paster, by working exclusively on the Apache configuration; clearly that is what you'll want to do if you've picked the flup/Apache/threaded combo.

At (roughly) the other extreme in the simplicity / functionality spectrum, I don't believe wsgiutils, out of the box, can be configured to use a thread pool (i.e., if I'm not mistaken, coding a new server kind around the minimal skeleton that wsgiutil provides would be needed to use a thread pool with it).

Clearly, if you need any kind of advanced configuration options, Apache's enormous power and flexibility are hard to beat:-).