title: What should I choose: MongoDB/Cassandra/Redis/CouchDB?
body: <p>We're developing a really big project and I was wondering if anyone can give me some advice about what DB backend should we pick.</p>
  
  <p>Our system is compound by 1100 electronic devices that send a signal to a central server and then the server stores the signal info (the signal is about 35 bytes long). How ever these devices will be sending about 3 signals per minute each, so if we do de numbers, that'll be 4.752.000 new records/day on the database, and a total of 142.560.000 new records/month.</p>
  
  <p>We need a DB Backend that is lighting fast and reliable. Of course we need to do some complex data mining on that DB. We're doing some research on the MongoDB/Cassandra/Redis/CouchDB, however the documentation websites are still on early stages.</p>
  
  <p>Any help? Ideas?</p>
  
  <p>Thanks a lot!</p>