Can I get a review of the branch? 25% performance improvement of Model.__init__ in stock django seems worth landing. :)
On Wed, Jul 18, 2012 at 3:48 AM, Jeremy Dunck <jdu...@gmail.com> wrote: > On Sun, Jul 15, 2012 at 11:07 AM, Jeremy Dunck <jdu...@gmail.com> wrote: >> >> That is indeed what I meant, but I think Anssi's probably right that >> this belongs in contribute_to_class instead of a new adhoc thing in >> ModelBase.__new__. >> >> I'll take a swing at making this change. >> >> Opened related ticket: https://code.djangoproject.com/ticket/18627 > > > OK, I have a very rough cut w/ all tests passing here: > https://github.com/jdunck/django/tree/18627_pre_init > > I poked in a flag, sys.JDUNCK_NEW, which can be turned on/off for old > and new implementation - this is poked in at django.__init__ > > To test performance, using tests/test_sqlite modified with: > > INSTALLED_APPS = [ > 'regressiontests.model_fields' > ] > > and > DATABASES['default']['name'] = ':memory:' > > Testing the pre_init hook: > > timeit.Timer(""" > for i in names: > models.Person(name=i) > """, """ > from django.core.management import call_command > from regressiontests.model_fields import models > call_command('syncdb') > names = [str(i) for i in range(1000)] > """).timeit(1000) > > Under the existing signal usage: 24.609718084335327 > Under the new approach avoiding signal usage: 18.074234008789062 > > I'd expect post_init to be a smaller gain since the destination > function has more overhead, but still a gain. > > Note that the pre_init and post_init signals are still fired -- it's > just that django as-shipped won't use any listeners on them, so the > Model.__init__ performance improves. > > In some cases, object construction currently is larger than query time > - a simple 'select x from y limit 1000' would have similar overhead to > this. Also, note that this gain would be seen on all models in any > project using GFK or ImageField but no other pre_init or post_init > hooks - not just those models which have the fields. With this > switch, only the models with the hooking fields have the related > overhead. > > Feedback welcome. -- You received this message because you are subscribed to the Google Groups "Django developers" group. To post to this group, send email to django-developers@googlegroups.com. To unsubscribe from this group, send email to django-developers+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-developers?hl=en.
