How Discord Scale

  • Switch from Cassandra to ScyllaDB which is written in C++

    • ScyllaDB is garbage collector free which reduce from the slowness of Cassandra
  • Discord use Terms/Request Coalescing which merge the requests together if they're querying the same server with the same content to reduce database hit.

  • Invented a concept of a Super Disk which can serve low latency read and durable write