MongoDB - Single Database or Multiple Databases for SaaS Offering

We have decided to use MongoDB for a SaaS offering we are creating. Each company that signs up gets their own url (mycompany.domain.com) and their own private set of users, projects, etc... Since we are using a NoSQL solution, and wouldn't have to manage pushing out schema updates to every database like we would with MySQL, I am wondering if it would be better to have one huge database containing all the data, or to have one database per client.

Since MongoDB can shard the database across multiple servers, I'm thinking there wouldn't be a huge performance hit if we had a giant开发者_如何学Go database, but I also think backups and exporting data would be much easier if there was one database per client. Any thoughts?

Go with one but make sure to take advantage of some sort of replication for backup purposes!

Look into sharding or look into replica-sets.