Enable pprof¶

net/http/pprof gives you live heap, goroutine, allocation, CPU and trace profiles — the tools you reach for when a long-running service leaks memory or goroutines. transport-metrics can mount it behind the same guard as /metrics.

It is off by default — pprof exposes rich internals, so turning it on is a deliberate choice.

Enable it¶

metrics.Register(mux,
    metrics.WithMiddleware(authMiddleware), // guards pprof too
    metrics.WithPprof(),
)

This mounts, under /debug/pprof/ (override with WithPprofPath):

Every one is wrapped by the middleware you passed — pprof is never exposed unguarded.

Use it¶

Point go tool pprof straight at the live endpoint (with whatever auth your guard needs, e.g. a bearer token via -H):

# a heap profile
go tool pprof http://localhost:8080/debug/pprof/heap

# 30s of CPU
go tool pprof http://localhost:8080/debug/pprof/profile?seconds=30

# goroutine dump in the browser
go tool pprof -http=: http://localhost:8080/debug/pprof/goroutine

Keep it off the open internet¶

Because pprof can dump memory contents and block the process (CPU/trace profiles), treat the guard as mandatory. For a local debugging aid, prefer a standalone metrics server bound to loopback so the profiles are reachable only from the host.