How Discord handles 850 MILLION messages / month 👩‍💻 #programming #programming #software #code

Key Takeaways

discord users send over 850 million messages a month how does discord handle this in 2015 discord needed to migrate to a more stable database but before choosing some research was needed to be done the read to write ratio on the database was 50 50. cassandra was the database of choice for its automatic failover low maintenance and predictable performance they structured it so that the last 10 days of messages is stored in a bucket so you can easily grab them fast they went live successfully within a week but then crashed because a server deleted millions of messages using the api cassandra uses something called a tombstone which means it hasn't deleted yet and skips the value well it retrieved millions and millions of tombstones they fixed this right away and went stable discord engineers are just incredible