Profiling Django app to figure out slow functions.
I just added some middleware to track function calls, following this blog: http://agiliq.com/blog/2015/07/profiling-django-middlewares/ and I see that the entry of cProfile stats for {posix.write} is one of the longest.
Any idea what that is, and where that comes from?
Other functions are referenced by their name and package path, so I'm not sure what {posix.write} means.
the log looks like this:
204051 function calls (197141 primitive calls) in 0.997 seconds
Ordered by: internal time
List reduced from 1204 to 50 due to restriction <50>
ncalls tottime percall cumtime percall filename:lineno(function)
35 0.305 0.009 0.305 0.009 {posix.write}
95 0.206 0.002 0.207 0.002 {method 'execute' of 'psycopg2.extensions.cursor' objects}
73 0.088 0.001 0.088 0.001 {select.select}
898 0.023 0.000 0.047 0.000 /.venv/lib/python2.7/site-packages/django/db/models/base.py:388(__init__)
1642 0.012 0.000 0.371 0.000 /.venv/lib/python2.7/site-packages/django/template/base.py:806(_resolve_lookup)
1 0.010 0.010 0.011 0.011 {_sass.compile_filename}
1 0.009 0.009 0.009 0.009 {psycopg2._psycopg._connect}
34 0.009 0.000 0.009 0.000 {method 'recv' of '_socket.socket' objects}
39 0.007 0.000 0.007 0.000 {posix.read}
9641/6353 0.006 0.000 0.321 0.000 {getattr}
173 0.006 0.000 0.026 0.000 /.venv/lib/python2.7/site-packages/django/core/urlresolvers.py:425(_reverse_with_prefix)
25769 0.006 0.000 0.007 0.000 {isinstance}
EDIT:
I understand that posix.write is the write function of posix. That I need to understand I guess is what part of Django uses that a lot and why it is showing up as taking 300+ms.
How would I go about tracking this down?
Thanks
