A case study in fanout, bottlenecks, and the engineering decisions behind Discord's scale.
The passive-sessions number is the one to remember: ~90% of connections in large servers didn't need the message at all. The biggest scaling win wasn't more machines or smarter parallelism, it was deleting work by asking "Who needs this right now?"
The passive-sessions number is the one to remember: ~90% of connections in large servers didn't need the message at all. The biggest scaling win wasn't more machines or smarter parallelism, it was deleting work by asking "Who needs this right now?"