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Go Benchmarks

test DOI Go Report Card License: MIT

In programming in general, and in Golang in particular, many roads lead to Rome. From time to time I ask myself which of these ways is the fastest. In Golang there is a wonderful solution, with go test -bench you can measure the speed very easily and quickly. In order for you to benefit from it too, I will publish such benchmarks in this repository in the future.

ToC

Golang?

I published another repository where I show some Golang examples. If you're interested in new programming languages, you should definitely take a look at Golang:

Is it any good?

Yes

Benchmark Results

Golang Version: go version go1.26.0 darwin/arm64
Hardware Spec: Apple MacBook Pro 16-Inch M2 Max 2023 (?) (buy)

base64

// Package base64 benchmarks some base64 functions.
// On all tested systems it's faster to decode a
// base64 encoded string instead of a check via regex.
package base64

import (
	"encoding/base64"
	"regexp"
	"testing"
)

func base64decode(s string) bool {
	_, err := base64.StdEncoding.DecodeString(s)
	return err == nil
}

func base64regex(s string) bool {
	matched, _ := regexp.MatchString(`^([A-Za-z0-9+/]{4})*([A-Za-z0-9+/]{4}|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{2}==)$`, s)
	return matched
}

func BenchmarkBase64decode(b *testing.B) {
	isNotBase64 := `Invalid string`
	isBase64 := `VmFsaWQgc3RyaW5nCg==`

	for n := 0; n < b.N; n++ {
		base64decode(isNotBase64)
		base64decode(isBase64)
	}
}

func BenchmarkBase64regex(b *testing.B) {
	isNotBase64 := `Invalid string`
	isBase64 := `VmFsaWQgc3RyaW5nCg==`

	for n := 0; n < b.N; n++ {
		base64regex(isNotBase64)
		base64regex(isBase64)
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/base64
cpu: Apple M2 Max
BenchmarkBase64decode-12    	18610372	        53.79 ns/op	      32 B/op	       2 allocs/op
BenchmarkBase64regex-12     	  129536	      8987 ns/op	   21885 B/op	     198 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/base64	2.633s

between

// Package between compares the performance of checking
// if a number is between two other numbers via regex
// and by parsing the number as integers.
package between

import (
	"regexp"
	"simonwaldherr.de/go/golibs/as"
	"simonwaldherr.de/go/ranger"
	"testing"
)

func BenchmarkNumberRegEx(b *testing.B) {
	re := ranger.Compile(89, 1001)
	re = "^(" + re + ")$"
	b.ResetTimer()

	for n := 0; n < b.N; n++ {
		matched, err := regexp.MatchString(re, "404")
		if !matched || err != nil {
			b.Log("Error in Benchmark")
		}

		matched, err = regexp.MatchString(re, "2000")
		if matched || err != nil {
			b.Log("Error in Benchmark")
		}
	}
}

func BenchmarkFulltextRegEx(b *testing.B) {
	re := ranger.Compile(89, 1001)
	re = " (" + re + ") "
	b.ResetTimer()

	for n := 0; n < b.N; n++ {
		matched, err := regexp.MatchString(re, "lorem ipsum 404 dolor sit")
		if !matched || err != nil {
			b.Log("Error in Benchmark")
		}

		matched, err = regexp.MatchString(re, "lorem ipsum 2000 dolor sit")
		if matched || err != nil {
			b.Log("Error in Benchmark")
		}
	}
}

func BenchmarkNumberParse(b *testing.B) {
	for n := 0; n < b.N; n++ {
		i1 := as.Int("404")
		i2 := as.Int("2000")

		if i1 < 89 || i1 > 1001 {
			b.Log("Error in Benchmark")
		}

		if !(i2 < 89 || i2 > 1001) {
			b.Log("Error in Benchmark")
		}
	}
}

func BenchmarkFulltextParse(b *testing.B) {
	re := regexp.MustCompile("[0-9]+")
	b.ResetTimer()

	for n := 0; n < b.N; n++ {
		i1 := as.Int(re.FindString("lorem ipsum 404 dolor sit"))
		i2 := as.Int(re.FindString("lorem ipsum 2000 dolor sit"))

		if i1 < 89 || i1 > 1001 {
			b.Log("Error in Benchmark")
		}

		if !(i2 < 89 || i2 > 1001) {
			b.Log("Error in Benchmark")
		}
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/between
cpu: Apple M2 Max
BenchmarkNumberRegEx-12      	  186266	      6243 ns/op	   16854 B/op	     142 allocs/op
BenchmarkFulltextRegEx-12    	  238280	      5013 ns/op	   12067 B/op	     104 allocs/op
BenchmarkNumberParse-12      	31805491	        38.09 ns/op	       0 B/op	       0 allocs/op
BenchmarkFulltextParse-12    	 2523129	       497.9 ns/op	      32 B/op	       2 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/between	5.817s

caseinsensitivecompare

package trim

import (
	"strings"
	"testing"
)

func BenchmarkEqualFold(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_ = strings.EqualFold("abc", "ABC")
		_ = strings.EqualFold("ABC", "ABC")
		_ = strings.EqualFold("1aBcD", "1AbCd")
	}
}

func BenchmarkToUpper(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_ = strings.ToUpper("abc") == strings.ToUpper("ABC")
		_ = strings.ToUpper("ABC") == strings.ToUpper("ABC")
		_ = strings.ToUpper("1aBcD") == strings.ToUpper("1AbCd")
	}
}

func BenchmarkToLower(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_ = strings.ToLower("abc") == strings.ToLower("ABC")
		_ = strings.ToLower("ABC") == strings.ToLower("ABC")
		_ = strings.ToLower("1aBcD") == strings.ToLower("1AbCd")
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/caseinsensitivecompare
cpu: Apple M2 Max
BenchmarkEqualFold-12    	71791442	        15.35 ns/op	       0 B/op	       0 allocs/op
BenchmarkToUpper-12      	11384388	       106.2 ns/op	      24 B/op	       3 allocs/op
BenchmarkToLower-12      	 8800382	       137.1 ns/op	      40 B/op	       5 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/caseinsensitivecompare	4.089s

concat

// Package concat benchmarks the performance of
// various string concatenation methods.
// Instead of just concatenating a string to another string
// it is also possible (and much faster) to use
// a bytes buffer.
package concat

import (
	"bytes"
	"strings"
	"testing"
)

func BenchmarkConcatString(b *testing.B) {
	var str string
	for n := 0; n < b.N; n++ {
		str += "x"
	}
}

func BenchmarkConcatBuffer(b *testing.B) {
	var buffer bytes.Buffer
	for n := 0; n < b.N; n++ {
		buffer.WriteString("x")

	}
}

func BenchmarkConcatBuilder(b *testing.B) {
	var builder strings.Builder
	for n := 0; n < b.N; n++ {
		builder.WriteString("x")
	}
}

func BenchmarkConcat(b *testing.B) {
	b.Run("String", func(b *testing.B) {
		var str string
		for n := 0; n < b.N; n++ {
			str += "x"
		}
	})

	b.Run("Buffer", func(b *testing.B) {
		var buffer bytes.Buffer
		for n := 0; n < b.N; n++ {
			buffer.WriteString("x")
		}
	})

	b.Run("Builder", func(b *testing.B) {
		var builder strings.Builder
		for n := 0; n < b.N; n++ {
			builder.WriteString("x")
		}
	})
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/concat
cpu: Apple M2 Max
BenchmarkConcatString-12     	 1000000	     30045 ns/op	  503993 B/op	       1 allocs/op
BenchmarkConcatBuffer-12     	330279432	         4.039 ns/op	       3 B/op	       0 allocs/op
BenchmarkConcatBuilder-12    	555759675	         2.555 ns/op	       5 B/op	       0 allocs/op
BenchmarkConcat/String-12    	 1000000	     29448 ns/op	  503993 B/op	       1 allocs/op
BenchmarkConcat/Buffer-12    	344907370	         3.522 ns/op	       3 B/op	       0 allocs/op
BenchmarkConcat/Builder-12   	560774194	         2.205 ns/op	       5 B/op	       0 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/concat	66.212s

contains

// Package contains tests various ways of checking
// if a string is contained in another string.
package contains

import (
	"bytes"
	"regexp"
	"strings"
	"testing"
)

// strings.Contains
func contains() bool {
	return strings.Contains("Lorem Ipsum", "em Ip")
}

func containsNot() bool {
	return strings.Contains("Lorem Ipsum", "Dolor")
}

func TestContains(t *testing.T) {
	if contains() == false {
		t.Error("ERROR: contains")
	}
	if containsNot() == true {
		t.Error("ERROR: contains not")
	}
}

func BenchmarkContains(b *testing.B) {
	for n := 0; n < b.N; n++ {
		contains()
	}
}

func BenchmarkContainsNot(b *testing.B) {
	for n := 0; n < b.N; n++ {
		containsNot()
	}
}

// bytes.Contains
func containsBytes() bool {
	return bytes.Contains([]byte("Lorem Ipsum"), []byte("em Ip"))
}

func containsBytesNot() bool {
	return bytes.Contains([]byte("Lorem Ipsum"), []byte("Dolor"))
}

func TestContainsBytes(t *testing.T) {
	if containsBytes() == false {
		t.Error("ERROR: bytes contains")
	}
	if containsBytesNot() == true {
		t.Error("ERROR: bytes contains not")
	}
}

func BenchmarkContainsBytes(b *testing.B) {
	for n := 0; n < b.N; n++ {
		containsBytes()
	}
}

func BenchmarkContainsBytesNot(b *testing.B) {
	for n := 0; n < b.N; n++ {
		containsBytesNot()
	}
}

// regexp.MustCompile + regexp.MatchString
func compileMatch(re *regexp.Regexp) bool {
	matched := re.MatchString("Lorem Ipsum")
	return matched
}

func compileMatchNot(re *regexp.Regexp) bool {
	matched := re.MatchString("Lorem Ipsum")
	return matched
}

func TestCompileMatch(t *testing.T) {
	re1 := regexp.MustCompile("em Ip")
	re2 := regexp.MustCompile("Dolor")
	if compileMatch(re1) == false {
		t.Error("ERROR: compile match")
	}
	if compileMatchNot(re2) == true {
		t.Error("ERROR: compile match not")
	}
}

func BenchmarkCompileMatch(b *testing.B) {
	re := regexp.MustCompile("em Ip")
	for n := 0; n < b.N; n++ {
		compileMatch(re)
	}
}

func BenchmarkCompileMatchNot(b *testing.B) {
	re := regexp.MustCompile("Dolor")
	for n := 0; n < b.N; n++ {
		compileMatchNot(re)
	}
}

// regexp.MatchString
func match() bool {
	matched, _ := regexp.MatchString("em Ip", "Lorem Ipsum")
	return matched
}

func matchNot() bool {
	matched, _ := regexp.MatchString("Dolor", "Lorem Ipsum")
	return matched
}

func TestMatch(t *testing.T) {
	if match() == false {
		t.Error("ERROR: match")
	}
	if matchNot() == true {
		t.Error("ERROR: match not")
	}
}

func BenchmarkMatch(b *testing.B) {
	for n := 0; n < b.N; n++ {
		match()
	}
}

func BenchmarkMatchNot(b *testing.B) {
	for n := 0; n < b.N; n++ {
		matchNot()
	}
}

// BenchmarkContainsMethods benchmarks different methods to check substring presence.
func BenchmarkContainsMethods(b *testing.B) {
	b.Run("Strings.Contains", func(b *testing.B) {
		str := "Lorem Ipsum"
		substr := "em Ip"
		for n := 0; n < b.N; n++ {
			_ = strings.Contains(str, substr)
			_ = strings.Contains(str, "Dolor")
		}
	})

	b.Run("Bytes.Contains", func(b *testing.B) {
		str := []byte("Lorem Ipsum")
		substr := []byte("em Ip")
		for n := 0; n < b.N; n++ {
			_ = bytes.Contains(str, substr)
			_ = bytes.Contains(str, []byte("Dolor"))
		}
	})

	b.Run("RegexMatchString", func(b *testing.B) {
		re := regexp.MustCompile(`em Ip`)
		for n := 0; n < b.N; n++ {
			_ = re.MatchString("Lorem Ipsum")
			_ = re.MatchString("Dolor")
		}
	})

	b.Run("RegexMatch", func(b *testing.B) {
		for n := 0; n < b.N; n++ {
			_, _ = regexp.MatchString(`em Ip`, "Lorem Ipsum")
			_, _ = regexp.MatchString(`em Ip`, "Dolor")
		}
	})
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/contains
cpu: Apple M2 Max
BenchmarkContains-12            	250304754	         4.833 ns/op	       0 B/op	       0 allocs/op
BenchmarkContainsNot-12         	209945680	         5.733 ns/op	       0 B/op	       0 allocs/op
BenchmarkContainsBytes-12       	222019953	         5.419 ns/op	       0 B/op	       0 allocs/op
BenchmarkContainsBytesNot-12    	181438317	         6.614 ns/op	       0 B/op	       0 allocs/op
BenchmarkCompileMatch-12        	26477133	        45.43 ns/op	       0 B/op	       0 allocs/op
BenchmarkCompileMatchNot-12     	50398551	        23.77 ns/op	       0 B/op	       0 allocs/op
BenchmarkMatch-12               	 1837810	       650.1 ns/op	    1396 B/op	      17 allocs/op
BenchmarkMatchNot-12            	 1962290	       613.3 ns/op	    1396 B/op	      17 allocs/op
BenchmarkContainsMethods/Strings.Contains-12         	100000000	        10.45 ns/op	       0 B/op	       0 allocs/op
BenchmarkContainsMethods/Bytes.Contains-12           	100000000	        11.14 ns/op	       0 B/op	       0 allocs/op
BenchmarkContainsMethods/RegexMatchString-12         	18116625	        65.87 ns/op	       0 B/op	       0 allocs/op
BenchmarkContainsMethods/RegexMatch-12               	  871435	      1286 ns/op	    2795 B/op	      34 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/contains	18.218s

concurrency_counter

package concurrency_counter

import (
	"fmt"
	"runtime"
	"sync"
	"sync/atomic"
	"testing"
)

// Benchmarks comparing common concurrency counter patterns.
// Variants:
// - sync.Mutex (write)
// - sync.RWMutex (write + read-heavy)
// - atomic.AddInt64
// - channels (various buffer sizes)
// - worker-pool (fixed workers consuming jobs)

func BenchmarkMutexParallel(b *testing.B) {
	var mu sync.Mutex
	var counter int64

	b.RunParallel(func(pb *testing.PB) {
		for pb.Next() {
			mu.Lock()
			counter++
			mu.Unlock()
		}
	})
}

func BenchmarkRWMutexWriteParallel(b *testing.B) {
	var mu sync.RWMutex
	var counter int64

	b.RunParallel(func(pb *testing.PB) {
		for pb.Next() {
			mu.Lock()
			counter++
			mu.Unlock()
		}
	})
}

func BenchmarkRWMutexReadParallel(b *testing.B) {
	var mu sync.RWMutex
	var counter int64

	// populate counter
	counter = 42

	b.RunParallel(func(pb *testing.PB) {
		for pb.Next() {
			mu.RLock()
			_ = counter
			mu.RUnlock()
		}
	})
}

func BenchmarkAtomicParallel(b *testing.B) {
	var counter int64

	b.RunParallel(func(pb *testing.PB) {
		for pb.Next() {
			atomic.AddInt64(&counter, 1)
		}
	})
}

func BenchmarkChannelBufferedSizes(b *testing.B) {
	sizes := []int{0, 1, 16, 1024}

	for _, sz := range sizes {
		b.Run(fmt.Sprintf("buf=%d", sz), func(b *testing.B) {
			ch := make(chan struct{}, sz)
			var wg sync.WaitGroup
			var counter int64

			wg.Add(1)
			go func() {
				for range ch {
					atomic.AddInt64(&counter, 1)
				}
				wg.Done()
			}()

			b.RunParallel(func(pb *testing.PB) {
				for pb.Next() {
					ch <- struct{}{}
				}
			})

			close(ch)
			wg.Wait()
		})
	}
}

func BenchmarkWorkerPool(b *testing.B) {
	workers := runtime.GOMAXPROCS(0)

	b.Run(fmt.Sprintf("workers=%d", workers), func(b *testing.B) {
		jobs := make(chan struct{}, 1024)
		var wg sync.WaitGroup
		var counter int64

		wg.Add(workers)
		for i := 0; i < workers; i++ {
			go func() {
				for range jobs {
					atomic.AddInt64(&counter, 1)
				}
				wg.Done()
			}()
		}

		b.RunParallel(func(pb *testing.PB) {
			for pb.Next() {
				jobs <- struct{}{}
			}
		})

		close(jobs)
		wg.Wait()
	})
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/concurrency_counter
cpu: Apple M2 Max
BenchmarkMutexParallel-12           	 8665891	       125.2 ns/op	       0 B/op	       0 allocs/op
BenchmarkRWMutexWriteParallel-12    	13164600	        92.21 ns/op	       0 B/op	       0 allocs/op
BenchmarkRWMutexReadParallel-12     	 8046151	       149.7 ns/op	       0 B/op	       0 allocs/op
BenchmarkAtomicParallel-12          	19512326	        58.12 ns/op	       0 B/op	       0 allocs/op
BenchmarkChannelBufferedSizes/buf=0-12         	 3335866	       354.5 ns/op	       0 B/op	       0 allocs/op
BenchmarkChannelBufferedSizes/buf=1-12         	 4314685	       281.2 ns/op	       0 B/op	       0 allocs/op
BenchmarkChannelBufferedSizes/buf=16-12        	 6826851	       173.8 ns/op	       0 B/op	       0 allocs/op
BenchmarkChannelBufferedSizes/buf=1024-12      	 9643142	       123.0 ns/op	       0 B/op	       0 allocs/op
BenchmarkWorkerPool/workers=12-12              	15753294	        68.32 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/concurrency_counter	12.278s

embed

package embed

import (
	_ "embed"
	"io/ioutil"
	"os"
	"testing"
)

//go:embed example.txt
var embeddedFile []byte

func BenchmarkEmbed(b *testing.B) {
	for i := 0; i < b.N; i++ {
		// Access the embedded file
		_ = embeddedFile
	}
}

func BenchmarkReadFile(b *testing.B) {
	for i := 0; i < b.N; i++ {
		// Read the file from disk
		data, err := os.ReadFile("example.txt")
		if err != nil {
			b.Fatalf("failed to read file: %v", err)
		}
		_ = data
	}
}

func BenchmarkIoutilReadFile(b *testing.B) {
	for i := 0; i < b.N; i++ {
		// Read the file using ioutil
		data, err := ioutil.ReadFile("example.txt")
		if err != nil {
			b.Fatalf("failed to read file: %v", err)
		}
		_ = data
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/embed
cpu: Apple M2 Max
BenchmarkEmbed-12             	1000000000	         0.3016 ns/op	       0 B/op	       0 allocs/op
BenchmarkReadFile-12          	  112020	     10550 ns/op	     840 B/op	       5 allocs/op
BenchmarkIoutilReadFile-12    	  114674	     10475 ns/op	     840 B/op	       5 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/embed	3.236s

floodfill

// Package floodfill benchmarks various flood fill implementations.
package main

import (
	"testing"
)

// Rekursive Implementierung
func floodFillRecursive(image [][]int, sr int, sc int, newColor int) [][]int {
	oldColor := image[sr][sc]
	if oldColor == newColor {
		return image
	}
	floodFillRecurse(image, sr, sc, oldColor, newColor)
	return image
}

func floodFillRecurse(image [][]int, sr int, sc int, oldColor int, newColor int) {
	if sr < 0 || sr >= len(image) || sc < 0 || sc >= len(image[0]) || image[sr][sc] != oldColor {
		return
	}
	image[sr][sc] = newColor

	floodFillRecurse(image, sr+1, sc, oldColor, newColor)
	floodFillRecurse(image, sr-1, sc, oldColor, newColor)
	floodFillRecurse(image, sr, sc+1, oldColor, newColor)
	floodFillRecurse(image, sr, sc-1, oldColor, newColor)
}

// Iterative Implementierung mit Stack (DFS)
func floodFillDFS(image [][]int, sr int, sc int, newColor int) [][]int {
	oldColor := image[sr][sc]
	if oldColor == newColor {
		return image
	}

	stack := [][]int{{sr, sc}}
	for len(stack) > 0 {
		current := stack[len(stack)-1]
		stack = stack[:len(stack)-1]

		r, c := current[0], current[1]
		if r < 0 || r >= len(image) || c < 0 || c >= len(image[0]) || image[r][c] != oldColor {
			continue
		}

		image[r][c] = newColor

		stack = append(stack, []int{r + 1, c})
		stack = append(stack, []int{r - 1, c})
		stack = append(stack, []int{r, c + 1})
		stack = append(stack, []int{r, c - 1})
	}
	return image
}

// Iterative Implementierung mit Queue (BFS)
func floodFillBFS(image [][]int, sr int, sc int, newColor int) [][]int {
	oldColor := image[sr][sc]
	if oldColor == newColor {
		return image
	}

	queue := [][]int{{sr, sc}}
	for len(queue) > 0 {
		current := queue[0]
		queue = queue[1:]

		r, c := current[0], current[1]
		if r < 0 || r >= len(image) || c < 0 || c >= len(image[0]) || image[r][c] != oldColor {
			continue
		}

		image[r][c] = newColor

		queue = append(queue, []int{r + 1, c})
		queue = append(queue, []int{r - 1, c})
		queue = append(queue, []int{r, c + 1})
		queue = append(queue, []int{r, c - 1})
	}
	return image
}

// Iterative Implementierung mit Stack (4-Wege-Verbindung)
func floodFillStack4Way(image [][]int, sr int, sc int, newColor int) [][]int {
	oldColor := image[sr][sc]
	if oldColor == newColor {
		return image
	}

	stack := [][]int{{sr, sc}}
	directions := [][]int{{1, 0}, {-1, 0}, {0, 1}, {0, -1}}
	for len(stack) > 0 {
		current := stack[len(stack)-1]
		stack = stack[:len(stack)-1]

		r, c := current[0], current[1]
		if r < 0 || r >= len(image) || c < 0 || c >= len(image[0]) || image[r][c] != oldColor {
			continue
		}

		image[r][c] = newColor

		for _, dir := range directions {
			stack = append(stack, []int{r + dir[0], c + dir[1]})
		}
	}
	return image
}

// Komplexes Beispielbild
var complexImage = [][]int{
	{0, 0, 0, 0, 0, 0},
	{0, 1, 1, 0, 1, 0},
	{0, 1, 0, 0, 1, 0},
	{0, 1, 1, 1, 1, 0},
	{0, 0, 0, 0, 0, 0},
	{0, 1, 1, 0, 1, 1},
}

// Benchmark für die rekursive Implementierung
func BenchmarkFloodFillRecursive(b *testing.B) {
	for i := 0; i < b.N; i++ {
		image := make([][]int, len(complexImage))
		for j := range complexImage {
			image[j] = make([]int, len(complexImage[j]))
			copy(image[j], complexImage[j])
		}
		floodFillRecursive(image, 1, 1, 2)
	}
}

// Benchmark für die iterative Implementierung mit Stack (DFS)
func BenchmarkFloodFillDFS(b *testing.B) {
	for i := 0; i < b.N; i++ {
		image := make([][]int, len(complexImage))
		for j := range complexImage {
			image[j] = make([]int, len(complexImage[j]))
			copy(image[j], complexImage[j])
		}
		floodFillDFS(image, 1, 1, 2)
	}
}

// Benchmark für die iterative Implementierung mit Queue (BFS)
func BenchmarkFloodFillBFS(b *testing.B) {
	for i := 0; i < b.N; i++ {
		image := make([][]int, len(complexImage))
		for j := range complexImage {
			image[j] = make([]int, len(complexImage[j]))
			copy(image[j], complexImage[j])
		}
		floodFillBFS(image, 1, 1, 2)
	}
}

// Benchmark für die iterative Implementierung mit Stack (4-Wege-Verbindung)
func BenchmarkFloodFillStack4Way(b *testing.B) {
	for i := 0; i < b.N; i++ {
		image := make([][]int, len(complexImage))
		for j := range complexImage {
			image[j] = make([]int, len(complexImage[j]))
			copy(image[j], complexImage[j])
		}
		floodFillStack4Way(image, 1, 1, 2)
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/floodfill
cpu: Apple M2 Max
BenchmarkFloodFillRecursive-12    	 5830284	       198.8 ns/op	     432 B/op	       7 allocs/op
BenchmarkFloodFillDFS-12          	 1411287	       807.1 ns/op	    1744 B/op	      48 allocs/op
BenchmarkFloodFillBFS-12          	 1000000	      1044 ns/op	    2704 B/op	      53 allocs/op
BenchmarkFloodFillStack4Way-12    	 1339846	       948.3 ns/op	    1744 B/op	      48 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/floodfill	6.904s

foreach

// Package foreach benchmarks ranging over slices and maps.
package foreach

import (
	"testing"
)

var amap map[int]string
var aslice []string

func init() {
	amap = map[int]string{
		0: "lorem",
		1: "ipsum",
		2: "dolor",
		3: "sit",
		4: "amet",
	}

	aslice = []string{
		"lorem",
		"ipsum",
		"dolor",
		"sit",
		"amet",
	}
}

func forMap() {
	for i := 0; i < len(amap); i++ {
		_ = amap[i]
	}
}

func rangeMap() {
	for _, v := range amap {
		_ = v
	}
}

func rangeSlice() {
	for _, v := range aslice {
		_ = v
	}
}

func rangeSliceKey() {
	for k := range aslice {
		_ = aslice[k]
	}
}

func BenchmarkForMap(b *testing.B) {
	for n := 0; n < b.N; n++ {
		forMap()
	}
}

func BenchmarkRangeMap(b *testing.B) {
	for n := 0; n < b.N; n++ {
		rangeMap()
	}
}

func BenchmarkRangeSlice(b *testing.B) {
	for n := 0; n < b.N; n++ {
		rangeSlice()
	}
}

func BenchmarkRangeSliceKey(b *testing.B) {
	for n := 0; n < b.N; n++ {
		rangeSliceKey()
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/foreach
cpu: Apple M2 Max
BenchmarkForMap-12           	63579042	        18.64 ns/op	       0 B/op	       0 allocs/op
BenchmarkRangeMap-12         	28603720	        42.01 ns/op	       0 B/op	       0 allocs/op
BenchmarkRangeSlice-12       	445286571	         2.708 ns/op	       0 B/op	       0 allocs/op
BenchmarkRangeSliceKey-12    	441072146	         2.707 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/foreach	6.490s

hash

// Package hash benchmarks various hashing algorithms.
// Especially with hashing algorithms, faster is not always better.
// One should always decide on the basis of the respective requirements.
package hash

import (
	"crypto/md5"
	"crypto/sha1"
	"crypto/sha256"
	"crypto/sha512"
	"hash"
	"hash/adler32"
	"hash/crc32"
	"hash/crc64"
	"hash/fnv"
	"math/rand"
	"testing"

	"github.com/jzelinskie/whirlpool"
	"github.com/reusee/mmh3"
	"github.com/zeebo/blake3"
	"golang.org/x/crypto/bcrypt"
	"golang.org/x/crypto/blake2b"
	"golang.org/x/crypto/md4"
	"golang.org/x/crypto/ripemd160"
	"golang.org/x/crypto/sha3"
)

func benchmarkHashAlgo(b *testing.B, h hash.Hash) {
	data := make([]byte, 2048)
	rand.Read(data)

	b.ResetTimer()
	for n := 0; n < b.N; n++ {
		h.Reset()
		h.Write(data)
		_ = h.Sum(nil)
	}
}

func benchmarkBCryptHashAlgo(b *testing.B, cost int) {
	data := make([]byte, 2048)
	rand.Read(data)

	b.ResetTimer()
	for n := 0; n < b.N; n++ {
		bcrypt.GenerateFromPassword(data, cost)
	}
}

func BenchmarkAdler32(b *testing.B) {
	benchmarkHashAlgo(b, adler32.New())
}

func BenchmarkBCryptCost4(b *testing.B) {
	benchmarkBCryptHashAlgo(b, 4)
}

func BenchmarkBCryptCost10(b *testing.B) {
	benchmarkBCryptHashAlgo(b, 10)
}

func BenchmarkBCryptCost16(b *testing.B) {
	benchmarkBCryptHashAlgo(b, 16)
}

/*
func BenchmarkBCryptCost22(b *testing.B) {
	benchmarkBCryptHashAlgo(b, 22)
}

func BenchmarkBCryptCost28(b *testing.B) {
	benchmarkBCryptHashAlgo(b, 28)
}

func BenchmarkBCryptCost31(b *testing.B) {
	benchmarkBCryptHashAlgo(b, 31)
}
*/

func BenchmarkBlake2b256(b *testing.B) {
	h, err := blake2b.New256(nil)
	if err != nil {
		b.Fatal(err)
	}
	benchmarkHashAlgo(b, h)
}

func BenchmarkBlake2b512(b *testing.B) {
	h, err := blake2b.New512(nil)
	if err != nil {
		b.Fatal(err)
	}
	benchmarkHashAlgo(b, h)
}

func BenchmarkBlake3256(b *testing.B) {
	benchmarkHashAlgo(b, blake3.New())
}

func BenchmarkMMH3(b *testing.B) {
	benchmarkHashAlgo(b, mmh3.New128())
}

func BenchmarkCRC32(b *testing.B) {
	benchmarkHashAlgo(b, crc32.NewIEEE())
}

func BenchmarkCRC64ISO(b *testing.B) {
	benchmarkHashAlgo(b, crc64.New(crc64.MakeTable(crc64.ISO)))
}

func BenchmarkCRC64ECMA(b *testing.B) {
	benchmarkHashAlgo(b, crc64.New(crc64.MakeTable(crc64.ECMA)))
}

func BenchmarkFnv32(b *testing.B) {
	benchmarkHashAlgo(b, fnv.New32())
}

func BenchmarkFnv32a(b *testing.B) {
	benchmarkHashAlgo(b, fnv.New32a())
}

func BenchmarkFnv64(b *testing.B) {
	benchmarkHashAlgo(b, fnv.New64())
}

func BenchmarkFnv64a(b *testing.B) {
	benchmarkHashAlgo(b, fnv.New64a())
}

func BenchmarkFnv128(b *testing.B) {
	benchmarkHashAlgo(b, fnv.New128())
}

func BenchmarkFnv128a(b *testing.B) {
	benchmarkHashAlgo(b, fnv.New128a())
}

func BenchmarkMD4(b *testing.B) {
	benchmarkHashAlgo(b, md4.New())
}

func BenchmarkMD5(b *testing.B) {
	benchmarkHashAlgo(b, md5.New())
}

func BenchmarkSHA1(b *testing.B) {
	benchmarkHashAlgo(b, sha1.New())
}

func BenchmarkSHA224(b *testing.B) {
	benchmarkHashAlgo(b, sha256.New224())
}

func BenchmarkSHA256(b *testing.B) {
	benchmarkHashAlgo(b, sha256.New())
}

func BenchmarkSHA384(b *testing.B) {
	benchmarkHashAlgo(b, sha512.New384())
}

func BenchmarkSHA512(b *testing.B) {
	benchmarkHashAlgo(b, sha512.New())
}

func BenchmarkSHA3256(b *testing.B) {
	benchmarkHashAlgo(b, sha3.New256())
}

func BenchmarkSHA3512(b *testing.B) {
	benchmarkHashAlgo(b, sha3.New512())
}

func BenchmarkRIPEMD160(b *testing.B) {
	benchmarkHashAlgo(b, ripemd160.New())
}

func BenchmarkWhirlpool(b *testing.B) {
	benchmarkHashAlgo(b, whirlpool.New())
}

func BenchmarkSHA256Parallel(b *testing.B) {
	b.RunParallel(func(pb *testing.PB) {
		data := make([]byte, 2048)
		rand.Read(data)
		for pb.Next() {
			h := sha256.New()
			h.Write(data)
			h.Sum(nil)
		}
	})
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/hash
cpu: Apple M2 Max
BenchmarkAdler32-12           	 1686130	       711.6 ns/op	       8 B/op	       1 allocs/op
BenchmarkBCryptCost4-12       	    1197	    986100 ns/op	    8166 B/op	       9 allocs/op
BenchmarkBCryptCost10-12      	      19	  60099759 ns/op	    8268 B/op	       9 allocs/op
BenchmarkBCryptCost16-12      	       1	3841080583 ns/op	    9976 B/op	      11 allocs/op
BenchmarkBlake2b256-12        	  466096	      2548 ns/op	      32 B/op	       1 allocs/op
BenchmarkBlake2b512-12        	  471380	      2556 ns/op	      64 B/op	       1 allocs/op
BenchmarkBlake3256-12         	  419404	      2920 ns/op	      32 B/op	       1 allocs/op
BenchmarkMMH3-12              	 3682060	       324.3 ns/op	      16 B/op	       1 allocs/op
BenchmarkCRC32-12             	 5020617	       238.9 ns/op	       8 B/op	       1 allocs/op
BenchmarkCRC64ISO-12          	 1000000	      1134 ns/op	       8 B/op	       1 allocs/op
BenchmarkCRC64ECMA-12         	 1000000	      1128 ns/op	       8 B/op	       1 allocs/op
BenchmarkFnv32-12             	  506677	      2419 ns/op	       8 B/op	       1 allocs/op
BenchmarkFnv32a-12            	  491040	      2429 ns/op	       8 B/op	       1 allocs/op
BenchmarkFnv64-12             	  492070	      2508 ns/op	       8 B/op	       1 allocs/op
BenchmarkFnv64a-12            	  502078	      2442 ns/op	       8 B/op	       1 allocs/op
BenchmarkFnv128-12            	  184444	      6469 ns/op	      24 B/op	       2 allocs/op
BenchmarkFnv128a-12           	  160760	      7444 ns/op	      24 B/op	       2 allocs/op
BenchmarkMD4-12               	  271032	      4453 ns/op	      16 B/op	       1 allocs/op
BenchmarkMD5-12               	  396086	      3077 ns/op	      16 B/op	       1 allocs/op
BenchmarkSHA1-12              	 1411992	       847.0 ns/op	      24 B/op	       1 allocs/op
BenchmarkSHA224-12            	 1377411	       861.5 ns/op	      32 B/op	       1 allocs/op
BenchmarkSHA256-12            	 1394524	       862.1 ns/op	      32 B/op	       1 allocs/op
BenchmarkSHA384-12            	  796393	      1495 ns/op	      48 B/op	       1 allocs/op
BenchmarkSHA512-12            	  793224	      1511 ns/op	      64 B/op	       1 allocs/op
BenchmarkSHA3256-12           	  213045	      5632 ns/op	     480 B/op	       2 allocs/op
BenchmarkSHA3512-12           	  120465	      9909 ns/op	     576 B/op	       3 allocs/op
BenchmarkRIPEMD160-12         	  199413	      6094 ns/op	      24 B/op	       1 allocs/op
BenchmarkWhirlpool-12         	   47091	     25393 ns/op	      64 B/op	       1 allocs/op
BenchmarkSHA256Parallel-12    	11684484	       107.2 ns/op	      32 B/op	       1 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/hash	42.788s

index

// Package index benchmarks access on maps with various data types as keys.
package index

import (
	"math/rand"
	"strconv"
	"testing"
)

var NumItems int = 1000000

var ms map[string]string
var ks []string

var mi map[int]string
var ki []int

func initMapStringIndex() {
	ms = make(map[string]string)
	ks = make([]string, 0)

	for i := 0; i < NumItems; i++ {
		key := strconv.Itoa(rand.Intn(NumItems))
		ms[key] = "value" + strconv.Itoa(i)
		ks = append(ks, key)
	}
}

func initMapIntIndex() {
	mi = make(map[int]string)
	ki = make([]int, 0)

	for i := 0; i < NumItems; i++ {
		key := rand.Intn(NumItems)
		mi[key] = "value" + strconv.Itoa(i)
		ki = append(ki, key)
	}
}

func init() {
	initMapStringIndex()
	initMapIntIndex()
}

func BenchmarkMapStringKeys(b *testing.B) {
	i := 0

	for n := 0; n < b.N; n++ {
		if _, ok := ms[ks[i]]; ok {
		}

		i++
		if i >= NumItems {
			i = 0
		}
	}
}

func BenchmarkMapIntKeys(b *testing.B) {
	i := 0

	for n := 0; n < b.N; n++ {
		if _, ok := mi[ki[i]]; ok {
		}

		i++
		if i >= NumItems {
			i = 0
		}
	}
}

func BenchmarkMapStringIndex(b *testing.B) {
	i := 0

	for n := 0; n < b.N; n++ {
		_ = ms[ks[i]]

		i++
		if i >= NumItems {
			i = 0
		}
	}
}

func BenchmarkMapIntIndex(b *testing.B) {
	i := 0

	for n := 0; n < b.N; n++ {
		_ = mi[ki[i]]

		i++
		if i >= NumItems {
			i = 0
		}
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/index
cpu: Apple M2 Max
BenchmarkMapStringKeys-12     	25108783	        44.50 ns/op	       0 B/op	       0 allocs/op
BenchmarkMapIntKeys-12        	69134380	        19.63 ns/op	       0 B/op	       0 allocs/op
BenchmarkMapStringIndex-12    	24572014	        46.70 ns/op	       0 B/op	       0 allocs/op
BenchmarkMapIntIndex-12       	62692188	        18.28 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/index	7.782s

json

package json

import (
	"encoding/json"
	"math"
	"math/big"
	"testing"
	"time"
)

type Data struct {
	String   string
	Time     time.Time
	Int      int
	Int8     int8
	Int16    int16
	Int32    int32
	Int64    int64
	Boolean  bool
	Float32  float32
	Float64  float64
	BigInt   big.Int
	BigFloat big.Float
}

func BenchmarkJsonMarshal(b *testing.B) {
	for n := 0; n < b.N; n++ {
		var d = Data{
			String:   "",
			Time:     time.Now(),
			Int:      math.MaxInt32,
			Int8:     math.MaxInt8,
			Int16:    math.MaxInt16,
			Int32:    math.MaxInt32,
			Int64:    math.MaxInt64,
			Boolean:  false,
			Float32:  math.MaxFloat32,
			Float64:  math.MaxFloat64,
			BigInt:   *big.NewInt(math.MaxInt64),
			BigFloat: *big.NewFloat(math.MaxFloat64),
		}

		_, err := json.Marshal(d)
		if err != nil {
			b.Error(err)
			b.Fail()
			return
		}
	}
}

func BenchmarkJsonUnmarshal(b *testing.B) {
	str := `
{
  "String": "",
  "Time": "2019-10-30T16:41:29.853426+07:00",
  "Int": 2147483647,
  "Int8": 127,
  "Int16": 32767,
  "Int32": 2147483647,
  "Int64": 9223372036854775807,
  "Boolean": false,
  "Float32": 3.4028235e+38,
  "Float64": 1.7976931348623157e+308,
  "BigInt": 9999999999999999999,
  "BigFloat": "2.7976931348623157e+308"
}
`

	for n := 0; n < b.N; n++ {
		var d Data
		err := json.Unmarshal([]byte(str), &d)
		if err != nil {
			b.Error(err)
			b.Fail()
			return
		}
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/json
cpu: Apple M2 Max
BenchmarkJsonMarshal-12      	 1612724	       710.0 ns/op	     480 B/op	       5 allocs/op
BenchmarkJsonUnmarshal-12    	  331173	      3669 ns/op	    1816 B/op	      27 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/json	3.255s

math

// Package math compares the speed of various mathematical operations.
package math

import (
	"sync"
	"sync/atomic"
	"testing"
)

func BenchmarkMathInt8(b *testing.B) {
	var intVal int8
	for n := 0; n < b.N; n++ {
		intVal = intVal + 2
	}
}

func BenchmarkMathInt32(b *testing.B) {
	var intVal int32
	for n := 0; n < b.N; n++ {
		intVal = intVal + 2
	}
}

func BenchmarkMathInt64(b *testing.B) {
	var intVal int64
	for n := 0; n < b.N; n++ {
		intVal = intVal + 2
	}
}

func BenchmarkMathAtomicInt32(b *testing.B) {
	var intVal int32
	for n := 0; n < b.N; n++ {
		atomic.AddInt32(&intVal, 2)
	}
}

func BenchmarkMathAtomicInt64(b *testing.B) {
	var intVal int64
	for n := 0; n < b.N; n++ {
		atomic.AddInt64(&intVal, 2)
	}
}

type IntMutex struct {
	v   int64
	mux sync.Mutex
}

func BenchmarkMathMutexInt(b *testing.B) {
	var m IntMutex
	for n := 0; n < b.N; n++ {
		m.mux.Lock()
		m.v = m.v + 2
		m.mux.Unlock()
	}
}

func BenchmarkMathFloat32(b *testing.B) {
	var floatVal float32
	for n := 0; n < b.N; n++ {
		floatVal = floatVal + 2
	}
}

func BenchmarkMathFloat64(b *testing.B) {
	var floatVal float64
	for n := 0; n < b.N; n++ {
		floatVal = floatVal + 2
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/math
cpu: Apple M2 Max
BenchmarkMathInt8-12           	1000000000	         0.3024 ns/op	       0 B/op	       0 allocs/op
BenchmarkMathInt32-12          	1000000000	         0.2998 ns/op	       0 B/op	       0 allocs/op
BenchmarkMathInt64-12          	1000000000	         0.2995 ns/op	       0 B/op	       0 allocs/op
BenchmarkMathAtomicInt32-12    	293730295	         4.131 ns/op	       0 B/op	       0 allocs/op
BenchmarkMathAtomicInt64-12    	266429888	         4.370 ns/op	       0 B/op	       0 allocs/op
BenchmarkMathMutexInt-12       	141521852	         8.509 ns/op	       0 B/op	       0 allocs/op
BenchmarkMathFloat32-12        	1000000000	         0.3022 ns/op	       0 B/op	       0 allocs/op
BenchmarkMathFloat64-12        	1000000000	         0.2993 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/math	7.294s

parse

// Package parse benchmarks parsing.
package parse

import (
	"strconv"
	"testing"
)

func BenchmarkParseBool(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := strconv.ParseBool("true")
		if err != nil {
			panic(err)
		}
	}
}

func BenchmarkParseInt(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := strconv.ParseInt("1337", 10, 64)
		if err != nil {
			panic(err)
		}
	}
}

func BenchmarkParseFloat(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := strconv.ParseFloat("3.141592653589793238462643383", 64)
		if err != nil {
			panic(err)
		}
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/parse
cpu: Apple M2 Max
BenchmarkParseBool-12     	504956373	         2.174 ns/op	       0 B/op	       0 allocs/op
BenchmarkParseInt-12      	100000000	        10.59 ns/op	       0 B/op	       0 allocs/op
BenchmarkParseFloat-12    	19408000	        62.18 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/parse	3.975s

random

// Package random compares math/rand with crypto/rand.
// math/rand is much faster than crypto/rand, but it
// returns only a pseudo random number.
package random

import (
	crand "crypto/rand"
	"encoding/base64"
	"math/big"
	mrand "math/rand"
	"testing"
)

func BenchmarkMathRand(b *testing.B) {
	for n := 0; n < b.N; n++ {
		mrand.Int63n(0xFFFF)
	}
}

func BenchmarkCryptoRand(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := crand.Int(crand.Reader, big.NewInt(0xFFFF))
		if err != nil {
			panic(err)
		}
	}
}

func BenchmarkCryptoRandString(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := GenerateRandomString(32)
		if err != nil {
			panic(err)
		}
	}
}

func BenchmarkCryptoRandBytes(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := GenerateRandomBytes(32)
		if err != nil {
			panic(err)
		}
	}
}

func GenerateRandomBytes(n int) ([]byte, error) {
	b := make([]byte, n)
	_, err := mrand.Read(b)
	if err != nil {
		return nil, err
	}

	return b, nil
}

func GenerateRandomString(s int) (string, error) {
	b, err := GenerateRandomBytes(s)
	return base64.URLEncoding.EncodeToString(b), err
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/random
cpu: Apple M2 Max
BenchmarkMathRand-12            	174362166	         6.810 ns/op	       0 B/op	       0 allocs/op
BenchmarkCryptoRand-12          	10414846	       114.5 ns/op	      48 B/op	       3 allocs/op
BenchmarkCryptoRandString-12    	10753096	       111.3 ns/op	     128 B/op	       3 allocs/op
BenchmarkCryptoRandBytes-12     	20317960	        61.86 ns/op	      32 B/op	       1 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/random	5.835s

regexp

// Package regexp benchmarks the performance of a pre-compiled regexp match
// a non-pre-compiled match and JIT-cached-compilation via golibs: https://simonwaldherr.de/go/golibs
package regexp

import (
	"regexp"
	"testing"

	"simonwaldherr.de/go/golibs/regex"
)

var regexpStr string = `^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,9}$`

func BenchmarkMatchString(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := regexp.MatchString(regexpStr, "john.doe@example.tld")
		if err != nil {
			panic(err)
		}
	}
}

func BenchmarkMatchStringCompiled(b *testing.B) {
	r, err := regexp.Compile(regexpStr)
	if err != nil {
		panic(err)
	}

	b.ResetTimer()
	for n := 0; n < b.N; n++ {
		r.MatchString("john.doe@example.tld")
	}
}

func BenchmarkMatchStringGolibs(b *testing.B) {
	for n := 0; n < b.N; n++ {
		_, err := regex.MatchString("john.doe@example.tld", regexpStr)
		if err != nil {
			panic(err)
		}
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/regexp
cpu: Apple M2 Max
BenchmarkMatchString-12            	  273990	      4024 ns/op	   10210 B/op	      86 allocs/op
BenchmarkMatchStringCompiled-12    	 3802354	       316.4 ns/op	       0 B/op	       0 allocs/op
BenchmarkMatchStringGolibs-12      	 3688004	       324.7 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/regexp	4.497s

sql

package main

import (
	"database/sql"
	"fmt"
	"testing"

	_ "modernc.org/sqlite"
)

func openSQLite(dsn string) (*sql.DB, error) {
	return sql.Open("sqlite", dsn)
}

// prepareSchema creates the users and orders tables used by benchmarks.
func prepareSchema(db *sql.DB) error {
	if _, err := db.Exec(`CREATE TABLE users (id INT, name TEXT, email TEXT, active BOOL)`); err != nil {
		return err
	}
	if _, err := db.Exec(`CREATE TABLE orders (id INT, user_id INT, amount FLOAT, status TEXT, meta JSON)`); err != nil {
		return err
	}
	return nil
}

func benchInsert(b *testing.B, open func(string) (*sql.DB, error), dsn string) {
	db, err := open(dsn)
	if err != nil {
		b.Fatalf("open: %v", err)
	}
	defer db.Close()

	if err := prepareSchema(db); err != nil {
		b.Fatalf("schema: %v", err)
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		tx, err := db.Begin()
		if err != nil {
			b.Fatalf("begin: %v", err)
		}
		stmt, err := tx.Prepare(`INSERT INTO users (id, name, email, active) VALUES (?, ?, ?, ?)`)
		if err != nil {
			b.Fatalf("prepare: %v", err)
		}
		if _, err := stmt.Exec(i, fmt.Sprintf("user%d", i), fmt.Sprintf("u%d@example.com", i), i%2 == 0); err != nil {
			b.Fatalf("exec: %v", err)
		}
		stmt.Close()
		if err := tx.Commit(); err != nil {
			b.Fatalf("commit: %v", err)
		}
	}
}

func benchSelectJoin(b *testing.B, open func(string) (*sql.DB, error), dsn string, rows int) {
	db, err := open(dsn)
	if err != nil {
		b.Fatalf("open: %v", err)
	}
	defer db.Close()

	if err := prepareSchema(db); err != nil {
		b.Fatalf("schema: %v", err)
	}

	// populate a modest dataset
	tx, err := db.Begin()
	if err != nil {
		b.Fatalf("begin: %v", err)
	}
	ustmt, _ := tx.Prepare(`INSERT INTO users (id, name, email, active) VALUES (?, ?, ?, ?)`)
	ostmt, _ := tx.Prepare(`INSERT INTO orders (id, user_id, amount, status, meta) VALUES (?, ?, ?, ?, ?)`)
	for i := 1; i <= rows; i++ {
		if _, err := ustmt.Exec(i, fmt.Sprintf("user%d", i), nil, true); err != nil {
			b.Fatalf("populate user: %v", err)
		}
		// attach a couple orders for each user
		for j := 0; j < 2; j++ {
			id := i*10 + j
			if _, err := ostmt.Exec(id, i, float64(id)*1.5, "PAID", `{"device":"web"}`); err != nil {
				b.Fatalf("populate order: %v", err)
			}
		}
	}
	ustmt.Close()
	ostmt.Close()
	if err := tx.Commit(); err != nil {
		b.Fatalf("commit populate: %v", err)
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		rows, err := db.Query(`
            SELECT u.name AS user, SUM(o.amount) AS total, COUNT(*) AS cnt
            FROM users u
            LEFT JOIN orders o ON u.id = o.user_id AND o.status = 'PAID'
            GROUP BY u.name
        `)
		if err != nil {
			b.Fatalf("query: %v", err)
		}
		for rows.Next() {
			var name string
			var total float64
			var cnt int
			if err := rows.Scan(&name, &total, &cnt); err != nil {
				b.Fatalf("scan: %v", err)
			}
		}
		rows.Close()
	}
}

func Benchmark_Insert_SQLite(b *testing.B) {
	// modernc.org/sqlite uses driver name "sqlite" and accepts a file: DSN
	benchInsert(b, openSQLite, "file::memory:?mode=memory&cache=shared")
}

func Benchmark_SelectJoin_SQLite(b *testing.B) {
	benchSelectJoin(b, openSQLite, "file::memory:?mode=memory&cache=shared", 200)
}
//go:build tinysql
// +build tinysql

package main

import (
	"database/sql"
	"testing"

	_ "github.com/SimonWaldherr/tinySQL/internal/driver"
)

func Benchmark_Insert_TinySQL(b *testing.B) {
	benchInsert(b, func(dsn string) (*sql.DB, error) { return sql.Open("tinysql", dsn) }, "mem://?tenant=bench")
}

func Benchmark_SelectJoin_TinySQL(b *testing.B) {
	benchSelectJoin(b, func(dsn string) (*sql.DB, error) { return sql.Open("tinysql", dsn) }, "mem://?tenant=bench_select", 200)
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/sql
cpu: Apple M2 Max
Benchmark_Insert_SQLite-12        	  125894	      9891 ns/op	     993 B/op	      27 allocs/op
Benchmark_SelectJoin_SQLite-12    	    2606	    473136 ns/op	   14824 B/op	    1212 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/sql	3.200s

sql (tinysql)

package main

import (
	"database/sql"
	"fmt"
	"testing"

	_ "modernc.org/sqlite"
)

func openSQLite(dsn string) (*sql.DB, error) {
	return sql.Open("sqlite", dsn)
}

// prepareSchema creates the users and orders tables used by benchmarks.
func prepareSchema(db *sql.DB) error {
	if _, err := db.Exec(`CREATE TABLE users (id INT, name TEXT, email TEXT, active BOOL)`); err != nil {
		return err
	}
	if _, err := db.Exec(`CREATE TABLE orders (id INT, user_id INT, amount FLOAT, status TEXT, meta JSON)`); err != nil {
		return err
	}
	return nil
}

func benchInsert(b *testing.B, open func(string) (*sql.DB, error), dsn string) {
	db, err := open(dsn)
	if err != nil {
		b.Fatalf("open: %v", err)
	}
	defer db.Close()

	if err := prepareSchema(db); err != nil {
		b.Fatalf("schema: %v", err)
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		tx, err := db.Begin()
		if err != nil {
			b.Fatalf("begin: %v", err)
		}
		stmt, err := tx.Prepare(`INSERT INTO users (id, name, email, active) VALUES (?, ?, ?, ?)`)
		if err != nil {
			b.Fatalf("prepare: %v", err)
		}
		if _, err := stmt.Exec(i, fmt.Sprintf("user%d", i), fmt.Sprintf("u%d@example.com", i), i%2 == 0); err != nil {
			b.Fatalf("exec: %v", err)
		}
		stmt.Close()
		if err := tx.Commit(); err != nil {
			b.Fatalf("commit: %v", err)
		}
	}
}

func benchSelectJoin(b *testing.B, open func(string) (*sql.DB, error), dsn string, rows int) {
	db, err := open(dsn)
	if err != nil {
		b.Fatalf("open: %v", err)
	}
	defer db.Close()

	if err := prepareSchema(db); err != nil {
		b.Fatalf("schema: %v", err)
	}

	// populate a modest dataset
	tx, err := db.Begin()
	if err != nil {
		b.Fatalf("begin: %v", err)
	}
	ustmt, _ := tx.Prepare(`INSERT INTO users (id, name, email, active) VALUES (?, ?, ?, ?)`)
	ostmt, _ := tx.Prepare(`INSERT INTO orders (id, user_id, amount, status, meta) VALUES (?, ?, ?, ?, ?)`)
	for i := 1; i <= rows; i++ {
		if _, err := ustmt.Exec(i, fmt.Sprintf("user%d", i), nil, true); err != nil {
			b.Fatalf("populate user: %v", err)
		}
		// attach a couple orders for each user
		for j := 0; j < 2; j++ {
			id := i*10 + j
			if _, err := ostmt.Exec(id, i, float64(id)*1.5, "PAID", `{"device":"web"}`); err != nil {
				b.Fatalf("populate order: %v", err)
			}
		}
	}
	ustmt.Close()
	ostmt.Close()
	if err := tx.Commit(); err != nil {
		b.Fatalf("commit populate: %v", err)
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		rows, err := db.Query(`
            SELECT u.name AS user, SUM(o.amount) AS total, COUNT(*) AS cnt
            FROM users u
            LEFT JOIN orders o ON u.id = o.user_id AND o.status = 'PAID'
            GROUP BY u.name
        `)
		if err != nil {
			b.Fatalf("query: %v", err)
		}
		for rows.Next() {
			var name string
			var total float64
			var cnt int
			if err := rows.Scan(&name, &total, &cnt); err != nil {
				b.Fatalf("scan: %v", err)
			}
		}
		rows.Close()
	}
}

func Benchmark_Insert_SQLite(b *testing.B) {
	// modernc.org/sqlite uses driver name "sqlite" and accepts a file: DSN
	benchInsert(b, openSQLite, "file::memory:?mode=memory&cache=shared")
}

func Benchmark_SelectJoin_SQLite(b *testing.B) {
	benchSelectJoin(b, openSQLite, "file::memory:?mode=memory&cache=shared", 200)
}
//go:build tinysql
// +build tinysql

package main

import (
	"database/sql"
	"testing"

	_ "github.com/SimonWaldherr/tinySQL/internal/driver"
)

func Benchmark_Insert_TinySQL(b *testing.B) {
	benchInsert(b, func(dsn string) (*sql.DB, error) { return sql.Open("tinysql", dsn) }, "mem://?tenant=bench")
}

func Benchmark_SelectJoin_TinySQL(b *testing.B) {
	benchSelectJoin(b, func(dsn string) (*sql.DB, error) { return sql.Open("tinysql", dsn) }, "mem://?tenant=bench_select", 200)
}
$ go test -bench . -benchmem -tags tinysql
# github.com/SimonWaldherr/golang-benchmarks/sql
bench_tinysql_test.go:10:2: no required module provides package github.com/SimonWaldherr/tinySQL/internal/driver; to add it:
	go get github.com/SimonWaldherr/tinySQL/internal/driver
FAIL	github.com/SimonWaldherr/golang-benchmarks/sql [setup failed]
(tinysql benchmarks skipped or failed)

template

// Package template benchmarks the performance of different templating methods
package template

import (
	"bytes"
	htmltemplate "html/template"
	"regexp"
	"testing"
	texttemplate "text/template"
)

// Define a struct to hold the data for the templates
type Data struct {
	Name    string
	Address string
}

// Prepare the templates and data
var (
	data = Data{Name: "John Doe", Address: "123 Elm St"}

	textTplString = "Name: {{.Name}}, Address: {{.Address}}"
	htmlTplString = "<div>Name: {{.Name}}</div><div>Address: {{.Address}}</div>"
	regExpString  = "Name: {{NAME}}, Address: {{ADDRESS}}"
)

// Benchmark for text/template
func BenchmarkTextTemplate(b *testing.B) {
	tpl, _ := texttemplate.New("text").Parse(textTplString)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		var buf bytes.Buffer
		tpl.Execute(&buf, data)
	}
}

// Benchmark for html/template
func BenchmarkHTMLTemplate(b *testing.B) {
	tpl, _ := htmltemplate.New("html").Parse(htmlTplString)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		var buf bytes.Buffer
		tpl.Execute(&buf, data)
	}
}

// Benchmark for replacing placeholders using regexp
func BenchmarkRegExp(b *testing.B) {
	rName := regexp.MustCompile(`{{NAME}}`)
	rAddress := regexp.MustCompile(`{{ADDRESS}}`)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		result := rName.ReplaceAllString(regExpString, data.Name)
		result = rAddress.ReplaceAllString(result, data.Address)
	}
}
$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/SimonWaldherr/golang-benchmarks/template
cpu: Apple M2 Max
BenchmarkTextTemplate-12    	 3534387	       335.9 ns/op	     272 B/op	       5 allocs/op
BenchmarkHTMLTemplate-12    	 1000000	      1048 ns/op	     496 B/op	      15 allocs/op
BenchmarkRegExp-12          	 2981480	       400.3 ns/op	     298 B/op	       9 allocs/op
PASS
ok  	github.com/SimonWaldherr/golang-benchmarks/template	4.504s