"However, the reason you're using Tornado is probably because it's much more performant that more convenient alternatives like Django". This is (or at least should be) false in the vast majority of the cases, if not all. Please if you want to be fast with Django it has its ways to go (a good way to start is reading the Book: High Performance Django). You use or should use Tornado for real time purposes in the 99,9% of the times, that is long polling, http2, websockets... something cannot be done (at least as good as Tornado or Twisted, although there're ways like gevent, channels...). Of course when you need asynchronous requests/processing or real-time streams you can and probably you should rely in ACID databases, no matter if it's MySQL, Postgresql or Rethinkdb. In the case of Postgresql, there a couple of libraries to wrap psycopg2 properly for tornado.
And before saying "if you have a huge number of requests per second you are not tied to the number of workers or the database I/O capacity" please consider that you are in the 0,01% or less of the cases. For the rest, keep in mind this: "don't use Tornado instead of Django (or WSGI, synchronous stack) because of performance, and even less droping ACID database for the very same reason".
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"However, the reason you're using Tornado is probably because it's much more performant that more convenient alternatives like Django". This is (or at least should be) false in the vast majority of the cases, if not all. Please if you want to be fast with Django it has its ways to go (a good way to start is reading the Book: High Performance Django). You use or should use Tornado for real time purposes in the 99,9% of the times, that is long polling, http2, websockets... something cannot be done (at least as good as Tornado or Twisted, although there're ways like gevent, channels...). Of course when you need asynchronous requests/processing or real-time streams you can and probably you should rely in ACID databases, no matter if it's MySQL, Postgresql or Rethinkdb. In the case of Postgresql, there a couple of libraries to wrap psycopg2 properly for tornado.
And before saying "if you have a huge number of requests per second you are not tied to the number of workers or the database I/O capacity" please consider that you are in the 0,01% or less of the cases. For the rest, keep in mind this: "don't use Tornado instead of Django (or WSGI, synchronous stack) because of performance, and even less droping ACID database for the very same reason".