Quick Julia Benchmarks

Run quick, impromptu benchmarks during development using BenchmarkTools.jl or Chairmarks.jl for ad-hoc performance measurements.

BenchmarkTools.jl (@btime)

The standard benchmarking tool with detailed statistics.

using BenchmarkTools

v = rand(1000)
@btime sum($v)          # Interpolate with $ to avoid global overhead

In-Place Operations

Use setup for functions that modify their input:

v = rand(1000)
@btime sort!(x) setup=(x=copy($v))  # Fresh copy each run

Comparing Implementations

v = rand(1000)
@btime sum($v)
@btime reduce(+, $v)

Chairmarks.jl (@b)

Lightweight alternative with automatic interpolation and faster startup.

using Chairmarks

v = rand(1000)
@b sum(v)               # Automatic interpolation (no $ needed)
@b sort!(x) setup=(x=copy($v))

Comparison Mode

@b sum(v) reduce(+, v)  # Compare two expressions

Quick Reference

Common Patterns

# Pure function
@btime f($x)

# Mutating function
@btime f!(y) setup=(y=copy($x))

# Multiple arguments
@btime f($x, $y, $z)

# Keyword arguments
@btime f($x; kwarg=$val)

Reference

• •Patterns - Common benchmarking patterns and pitfalls

Related Skills

• •julia-bench-write - Writing benchmark suites
• •julia-bench-run - Running benchmark suites