This is a technical dive into how we split our data across many MySQL servers. We finished launching this sharding approach in early 2012, and it’s still the system we use today to store our core data.

After using a bunch of methods to scale like R/W split, MySQL partitioning and witnessing them being inadequate for our rapid growth, we came to the conclusion that scaling vertically can only get you so far. The more we thought about it, the more it made sense for us to shard our database.