I know the reddit guys, and I can tell you it's definitely not that. Hitting the DB is extremely rare - almost everything comes straight out of cache (either me

I know the reddit guys, and I can tell you it's definitely not that. Hitting the DB is extremely rare - almost everything comes straight out of cache (either memcache, or memcachedb for caches which are more expensive to rebuild). Execution cost is dominated by the python app servers.