go-fast-date

Go port of A Very Fast 64–Bit Date Algorithm, based on A Very Fast 64–Bit Date Algorithm: 30–40% faster by Ben Joffe. Special thanks to @benjoffe for writing such an easy to follow blog post and implementation.

Usage

go get github.com/xnacly/go-fast-date

package main

import (
	"fmt"
	"time"

	"github.com/xnacly/go-fast-date"
)

func main() {
	date := gofastdate.FromUnix(time.Now().Unix())
	fmt.Println(date)

	fmt.Println(date.Time())
	fmt.Println(date.Unix(), date.Time().Unix())
}

Features

go-fast-date implements Ben Joffe's very fast 64-bit date algorithm and provides date round trip functions for time.Time compatibility:

• gofastdate.FromUnix
• gofastdate.FromTime
• gofastdate.Date.Time
• gofastdate.Date.Unix

While not depending on any dependency and striving to match Joffe's implementation, where applicable.

Benchmarks

Benchmarks focus on comparing gofastdate.FromUnix with time.Unix. Run with go test ./... -bench=.

Low end hardware:

• micro benchmark: fastdate ~13% faster
• stress: fastdate ~4.2x faster (8.98ms vs 37.38ms)

goos: linux
goarch: amd64
pkg: github.com/xnacly/go-fast-date
cpu: Intel(R) Core(TM) i5-3210M CPU @ 2.50GHz
BenchmarkTimeUnix-4                     21141045                56.21 ns/op
BenchmarkGoFastDateUnix-4               24253924                48.90 ns/op
BenchmarkStressTimeUnixToDate-4               32             37382839 ns/op
BenchmarkStressGoFastDateFromUnix-4          132              8977516 ns/op
PASS
ok      github.com/xnacly/go-fast-date  6.369s

Mid end hardware:

• micro benchmark: fastdate ~32% faster
• stress: fastdate ~4.1x faster (5.16ms vs 21.41ms)

goos: linux
goarch: amd64
pkg: github.com/xnacly/go-fast-date
cpu: AMD Ryzen 7 3700X 8-Core Processor
BenchmarkTimeUnix-16                            35375085                37.20 ns/op
BenchmarkGoFastDateUnix-16                      47718576                25.21 ns/op
BenchmarkStressTimeUnixToDate-16                      56             21414260 ns/op
BenchmarkStressGoFastDateFromUnix-16                 232              5158183 ns/op
PASS
ok      github.com/xnacly/go-fast-date  5.463s