debug_timer_log.py

# in my settings_local.py
import datetime
import logging

from django.http import HttpRequest


class TimingHandler(logging.Handler):

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        from django.core.signals import request_started
        request_started.connect(self.reset_q)
        if not hasattr(HttpRequest, 'timinglog'):
            import threading
            HttpRequest.timinglog = threading.local()

    def reset_q(self, **kwargs):
        HttpRequest.timinglog.q = []
        HttpRequest.timinglog.start = datetime.datetime.now()

    def emit(self, record):
        if hasattr(HttpRequest.timinglog, 'q'):
            diff = datetime.datetime.now() - HttpRequest.timinglog.start
            HttpRequest.timinglog.q.append((diff.seconds * 1000 + diff.microseconds / 1000., record.getMessage()))

timing = TimingHandler()
logging.basicConfig(level=logging.DEBUG, handlers=[timing])
LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'handlers': {'console': {'class': 'logging.StreamHandler'}, 'timing': {'class': 'settings_local.TimingHandler'}},
    'loggers': {
        '*': {'handlers': ['console'], 'level': 'DEBUG'},
        'django': {'handlers': ['console'], 'level': 'DEBUG'},
    },
}

# at the bottom of my common template:
'''
{% if request.timinglog %}
<style>
.timings span {
    background-color: white;
    height: 3em;
    position: absolute;
    width: 1px;
}
</style>
<div class="timings">
{% for ms, msg in request.timinglog.q %}
<span style="left: {{ ms }}px" title="{{ msg }}"></span>
{% endfor %}
</div>
{% endif %}
'''