bench

Reliable performance measurement for Go programs. All in one design.

$ go install golang.design/x/bench@latest

Features

• Combine benchstat, perflock and more...
• Short command and only run benchmarks
• Automatic performance locking for benchmarks
• Automatic statistic analysis for benchmark results
• Color indications for benchmark results

Usage

Enable bench Daemon (optional, Linux only)

$ cd $GOPATH/src/golang.design/x/bench
$ ./install.bash

If your init system is supported, this will also configure bench to start automatically on boot.

Or you can install and run bench daemon manually:

$ sudo install $GOPATH/bin/bench /usr/bin/bench
$ sudo -b bench -daemon

Default Behavior

$ bench

The detault behavior of bench run benchmarks under your current working directory, and each benchmark will be ran 10 times for further statistical analysis. It will also try to acquire performance lock from bench daemon to gain more stable results. Furthermore, the benchmark results are saved as a text file to the working directory and named as <timestamp>.txt.

Example:

$ cd example
$ bench
bench: run benchmarks under 90% cpufreq...
bench: go test -run=^$ -bench=. -count=10
goos: linux
goarch: amd64
pkg: golang.design/x/bench/example
BenchmarkDemo-16           21114             57340 ns/op
...
BenchmarkDemo-16           21004             57097 ns/op
PASS
ok      golang.design/x/bench/example   17.791s
bench: results are saved to file: ./bench-2020-11-07-19:59:51.txt

name     time/op
Demo-16  57.0µs ±1%

$ # ... do some changes to the benchmark ...

$ bench
bench: run benchmarks under 90% cpufreq...
bench: go test -run=^$ -bench=. -count=10
goos: linux
goarch: amd64
pkg: golang.design/x/bench/example
BenchmarkDemo-16          213145              5625 ns/op
...
BenchmarkDemo-16          212959              5632 ns/op
PASS
ok      golang.design/x/bench/example   12.536s
bench: results are saved to file: ./bench-2020-11-07-20:00:16.txt

name     time/op
Demo-16  5.63µs ±0%

$ bench bench-2020-11-07-19:59:51.txt bench-2020-11-07-20:00:16.txt
name     old time/op new time/op  delta
Demo-16  57.0µs ±1%  5.6µs ±0%   -90.13%  (p=0.000 n=10+8)

Options

Options for checking daemon status:

bench -list

Options for statistic tests:

bench old.txt [new.txt]             # same from benchstat
bench -delta-test
bench -alpha
bench -geomean
bench -split
bench -sort

Options for running benchmarks:

bench -v                            # enable verbose outputs
bench -shared                       # enable shared execution
bench -cpufreq 90                   # cpu frequency             (default: 90)
bench -name BenchmarkXXX            # go test `-bench` flag     (default: .)
bench -count 20                     # go test `-count` flag     (default: 10)
bench -time 100x                    # go test `-benchtime` flag (default: unset)
bench -cpuproc 1,2,4,8,16,32,128    # go test `-cpu` flag       (default: unset)

License

© 2020 The golang.design Authors