Foursquare outage post mortem

Foursquare outage post mortem

It seems that mongodb is quite slow that Foursquare needs to
put all the data in RAM to get an acceptable performance.
This is simply CRAZY.

date: Fri, Oct 8, 2010 at 1:18 PM (7 days ago)
subject: Re: Foursquare MongoDB outage

I didn't realize that Foursquare has so many data and runs
too slow when the data is on disk! This is a bit crazy,
they'll need to add machines and RAMs endlessly...

I think they might need better distributed database
(e.g. cassandra?) instead of sharding themselves.