How to Monitor GC Performance in Go

You monitor Go garbage collector (GC) performance by enabling the GODEBUG environment variable to print GC statistics to stderr. Set GODEBUG=gctrace=1 before running your application to see real-time metrics like pause times, heap usage, and GC cycles.

export GODEBUG=gctrace=1
go run main.go

Alternatively, use the runtime/metrics package in your code to programmatically access GC metrics like cgo/go/gc/cycles or cgo/go/gc/pauses without relying on environment variables.

Monitoring GC Performance in Go lets you see how often and how long your program stops to clean up unused memory. Think of it like a dashboard for your program's housekeeping crew, showing you when they take a break and how much work they did. You use it when your app feels slow or lags unexpectedly to see if memory cleanup is the cause.