middleware.py

# encoding: utf-8
# Derived from Piotr Maliński's example with a few modifications to use logging and :
# http://www.rkblog.rk.edu.pl/w/p/profiling-django-object-size-and-memory-usage-pympler/

from pympler.muppy import muppy
from pympler.muppy import summary
from pympler.asizeof import asizeof
from django.conf import settings

import logging

class MemoryMiddleware(object):
    """
    Measure memory taken by requested view, and response
    """
    def process_request(self, request):
        path = request.META['PATH_INFO']
        if "media" in path or settings.MEDIA_URL in path:
            return
            
        self.start_objects = muppy.get_objects()
        
    def process_response(self, request, response):
        path = request.META['PATH_INFO']
        if "media" in path or settings.MEDIA_URL in path:
            return response

        self.end_objects = muppy.get_objects()

        sum_start = summary.summarize(self.start_objects)
        sum_end   = summary.summarize(self.end_objects)
        diff      = summary.get_diff(sum_start, sum_end)
        
        logging.info("Top 10 memory deltas after processing %s", path)
        logging.info("%-60s %10s %10s", "type", "# objects", "total size")

        for row in sorted(diff, key=lambda i: i[2], reverse=True)[:10]:
            logging.info("%60s %10d %10d", *row)

        start_size = asizeof(self.start_objects)
        end_size   = asizeof(self.end_objects)

        logging.info(
            "Processed %s: memory delta %0.1f kB (%0.1f -> %0.1fMB), response size: %0.1f kB",
            path,
            (end_size - start_size) / 1024.0,
            start_size / 1048576.0,
            end_size / 1048576.0,
            len(response.content)  / 1024.0,
        )

        return response