We (Discord) moved off of MongoDB for various reasons and are quite happy about that decision but managing Cassandra/Scylla clusters is not exactly a walk in the park either.
I didn't make the original decision but if I were starting something and I had no idea whether or not it'd be successful, I'd do whatever was the absolute fastest way to get to MVP. That'd probably be a cloud database, honestly -- but a modern MongoDB would be technically fine too (licensing stuff notwithstanding.)
Most startups fail not because they picked a suboptimal database for their usage but because they didn't build something that was good or it didn't achieve product market fit. I wouldn't worry about your database over-much in the beginning (unless it's critical to what you're doing and in that case, worry like hell, but you will probably know if that's the case.)
Many of Discord's issues with Mongo were exacerbated that we were using TokuMX which was abandoned shortly after we started using it. A few years into Discord we found ourselves with a rapidly scaling dataset and userbase that was built on top of an abandoned and not super popular third party version of MongoDB. (Funny story: at one point towards the end we realized that all of the packages had been pulled from every mirror we could find and literally the only place we could find the package files was off of some gov.uk mirror... that was a bad day. Thankfully we had the hashes and were able to validate the packages...)
FWIW, we did honestly debate moving our core user model (which was what was left in TokuMX by the end there) into a modern version of MongoDB -- some of the things we did (reverse indexes, secondary indexes, locking, etc) are much more complicated in a database like Scylla. It was tempting to just migrate the data from one "Mongo" to another and call it a day.
We didn't for a variety reasons, not least of which is keeping things simple by reducing the number of technologies you have in production (like when we chose to embrace Rust we went back and migrated nearly all of our Go systems).
Anyway, I'm pretty happy with not running MongoDB anymore, but not because MongoDB is inherently bad. It's popular for a reason!
rusht|4 years ago
zorkian|4 years ago
Most startups fail not because they picked a suboptimal database for their usage but because they didn't build something that was good or it didn't achieve product market fit. I wouldn't worry about your database over-much in the beginning (unless it's critical to what you're doing and in that case, worry like hell, but you will probably know if that's the case.)
Many of Discord's issues with Mongo were exacerbated that we were using TokuMX which was abandoned shortly after we started using it. A few years into Discord we found ourselves with a rapidly scaling dataset and userbase that was built on top of an abandoned and not super popular third party version of MongoDB. (Funny story: at one point towards the end we realized that all of the packages had been pulled from every mirror we could find and literally the only place we could find the package files was off of some gov.uk mirror... that was a bad day. Thankfully we had the hashes and were able to validate the packages...)
FWIW, we did honestly debate moving our core user model (which was what was left in TokuMX by the end there) into a modern version of MongoDB -- some of the things we did (reverse indexes, secondary indexes, locking, etc) are much more complicated in a database like Scylla. It was tempting to just migrate the data from one "Mongo" to another and call it a day.
We didn't for a variety reasons, not least of which is keeping things simple by reducing the number of technologies you have in production (like when we chose to embrace Rust we went back and migrated nearly all of our Go systems).
Anyway, I'm pretty happy with not running MongoDB anymore, but not because MongoDB is inherently bad. It's popular for a reason!