How would one make Python objects persistent in a web-app?

Question

I\'m writing a reasonably complex web application. The Python backend runs an algorithm whose state depends on data stored in several interrelated database tables which does not

Answer 1

First of all your approach is not a common web development practice. Even multi threading is being used, web applications are designed to be able to run multi-processing environments, for both scalability and easier deployment .

If you need to just initialize a large object, and do not need to change later, you can do it easily by using a global variable that is initialized while your WSGI application is being created, or the module contains the object is being loaded etc, multi processing will do fine for you.

If you need to change the object and access it from every thread, you need to be sure your object is thread safe, use locks to ensure that. And use a single server context, a process. Any multi threading python server will serve you well, also FCGI is a good choice for this kind of design.

But, if multiple threads are accessing and changing your object the locks may have a really bad effect on your performance gain, which is likely to make all the benefits go away.