Profiling Django

Question

My django application has become painfully slow on the production. Prolly it is due to some complex or unindexed queries.

Is there any django-ish way to profile my application?

Answer 1

Try "Django Toolbar": http://github.com/robhudson/django-debug-toolbar It will show you what queries are executed on each page and how much time they take. A really useful, powerful and easy to use tool.

Also, read recommendations about Django performance in docs: http://docs.djangoproject.com/en/dev/topics/db/optimization/

And here: http://jacobian.org/writing/django-performance-tips/

Answer 2

Just type "django-profiling" on google, you'll get these links (and more):

http://code.djangoproject.com/wiki/ProfilingDjango

http://code.google.com/p/django-profile/

http://www.rkblog.rk.edu.pl/w/p/django-profiling-hotshot-and-kcachegrind/

Personally I'm using middleware approach - i.e. each user can toggle "profiling" flag stored in session, and if my profiling middleware notices that flag being set, it uses Python's hotshot module like this:

def process_view(self, request, view_func, view_args, view_kwargs):

     # setup things here, along with: settings.DEBUG=True 
     # to get SQL dump in connection.queries

     profiler = hotshot.Profile(fname)
     response = profiler.runcall(view_func, request, *view_args, **view_kwargs)
     profiler.close()

     # process results

     return response

EDIT: For profiling SQL queries http://github.com/robhudson/django-debug-toolbar mentioned by Konstantin is a nice thing - but if your queries are really slow (probably because there are hundres or thousends of them), then you'll be waiting insane amounts of time until it gets loaded into browser - and then it'll be hard to browse due to slowliness. Also, django-debug-toolbar is by design unable to give an useful insight into the internals of AJAX requests.