Benchmarking Skill

Name: benchmarking
Rating: 78
Author: MolcajeteAI

Performance benchmarking techniques for Go.

When to Use

Use when measuring or comparing performance.

Writing Benchmarks

func BenchmarkGetUser(b *testing.B) {
    svc := NewService()
    ctx := context.Background()

    b.ResetTimer()
    for i := 0; i < b.N; i++ {
        _, _ = svc.GetUser(ctx, 1)
    }
}

Running Benchmarks

bash

# Run all benchmarks
go test -bench=. -benchmem ./...

# Specific benchmark
go test -bench=BenchmarkGetUser -benchmem

# Multiple runs for accuracy
go test -bench=. -benchmem -count=10

Analyzing Results

code

BenchmarkGetUser-8    1000000    1250 ns/op    320 B/op    5 allocs/op

•1000000 - iterations
•1250 ns/op - time per operation
•320 B/op - bytes allocated
•5 allocs/op - allocations per operation

Comparing with benchstat

bash

go test -bench=. -count=10 > old.txt
# make changes
go test -bench=. -count=10 > new.txt
benchstat old.txt new.txt

Best Practices

•Use b.ResetTimer() after setup
•Run multiple times (-count)
•Use benchstat for comparison
•Focus on allocations
•Profile to understand results