Django. Business Logic Bottlenecks.
Do you use the django debug toolbar ? You could find what queries are run with it, middleware or not.
How do you monitor the performance of the view ?
Are there much more users in the big project than in the fresh one ?
Is there any smart way to find bottlenecks in business logic. For example, we have application, that have one view that doing HttpResponse('1') in big project. We are sure, that no SQL queries in middlewares exists. But HttpResponse working really slow(50 rps vs 200 rps on clear django project). 

What reasons can be?
How to find bottlenecks in this case? 
Also we know, that in clear project less than 1 Mb of memory used for objects on each request, and in our project - more than 2Mb. How to find these objects?