use pylibmc, go fast (bug 564105)

docs/settings/settings_local.prod.py

@@ -29,7 +29,7 @@ DATABASES = {
 SLAVE_DATABASES = ['slave']
 
 # Use IP:PORT pairs separated by semicolons.
-CACHE_BACKEND = 'caching.backends.memcached://localhost:11211;localhost:11212?timeout=500'
+CACHE_BACKEND = 'django_pylibmc.memcached://localhost:11211;localhost:11212?timeout=500'
 
 # This is used to hash some things in Django.
 SECRET_KEY = 'replace me with something long'

requirements-prod.txt

@@ -13,6 +13,9 @@ celery==1.0.2
 # packaging doesn't pick it up.
 importlib==1.0.2
 
+pylibmc==1.0
+django-pylibmc==0.1
+
 -e git://github.com/jbalogh/django-multidb-router.git#egg=django-multidb-router
 -e git://github.com/jbalogh/django-cache-machine.git#egg=django-cache-machine
 -e git://github.com/jbalogh/jingo.git#egg=jingo