http://blog.getspool.com/2011/11/29/fast-easy-realtime-metri...
And the HN posts / comments:
https://news.ycombinator.com/item?id=3292542 http://news.ycombinator.com/item?id=3748239
And the Redis warning on setting large bitmaps (Re: split your bitmaps):
http://redis.io/commands/setbit
Note: I know I'm responding to someone who is probably already aware of this information, but the crashly slides are lite on the techniques technical side.