---

name: performance-profiling description: pprof usage and performance analysis. Use when profiling applications.

Performance Profiling Skill

Using pprof for performance analysis.

When to Use

Use when identifying performance bottlenecks.

CPU Profiling

Copy# During tests
go test -cpuprofile=cpu.out -bench=.

# Analyze
go tool pprof cpu.out

# Web interface
go tool pprof -http=:8080 cpu.out

Memory Profiling

Copy# During tests
go test -memprofile=mem.out -bench=.

# Analyze
go tool pprof mem.out

HTTP Endpoint

Copyimport _ "net/http/pprof"

func main() {
    go func() {
        log.Println(http.ListenAndServe("localhost:6060", nil))
    }()
    // your code
}

Access profiles at:

• http://localhost:6060/debug/pprof/
• http://localhost:6060/debug/pprof/heap
• http://localhost:6060/debug/pprof/goroutine

pprof Commands

Copy(pprof) top      # Top functions
(pprof) list     # Source code view
(pprof) web      # Graph view
(pprof) pdf      # PDF output

Best Practices

• Profile in production-like conditions
• Profile before optimizing
• Focus on hot paths
• Check both CPU and memory
• Use flamegraphs for visualization