How to Handle 10,000 WebSocket Connections in Go
· 10 min read
"Can it handle 10,000 connections?" gets asked about every realtime service, usually as a stand-in for "is this production-grade." It's the wrong question in one specific way: for a Go server, holding 10,000 idle-ish WebSocket connections open was never the hard part. The C10K problem — the one that gave the number its mythology — was about thread-per-connection servers where each connection cost an OS thread and a context switch. Go's runtime solved that structurally before you wrote a line of your handler. What's left is arithmetic: how much memory each connection actually costs, and which OS limits you'll hit before your own code does.