django+uwsgi huge excessive memory usage issue

After some digging on stackflow and google search, here is the solution.

• read this how django memory works and why it keeps going up
• read this django app profiling

then I figured out the major parameter to set in uwsgi.ini is max_request. originally, I set it as 2000. now set it as 50. so it will respawn workers when memory goes up too much. Then i try to figure out which request causes huge data query results from database. I ended up finding this little line:

  amount=sum(x.amount for x in Project.objects.all()) 

While Project table has over 1 million complex entries.Occupying huge memory.... since I commented this out... everything runs smooth now.

So it is good to understand how the [django query works with database]