Test mysql link speed over various DSN with SELECT NOW()

mysqlnowspeed.go

// Test mysql speed over various DSN with SELECT NOW()
//
// Build with:
// 	// make an empty folder and cd into
// 	export GOPATH=`pwd`
// 	go get gist.github.com/e792f270bb6bc93a2a671bb7519d5417.git
// 	// or, for cross-build:
// 	env GOOS=linux GOARCH=amd64 go build -v gist.github.com/e792f270bb6bc93a2a671bb7519d5417.git
package main

import "os"
import "time"
import "fmt"
import "strconv"
import "database/sql"
import _ "github.com/go-sql-driver/mysql"

func runBench01Now(loopCount int, dsnText string) (queryLoopCost time.Duration, err error) {
	dbconn, err := sql.Open("mysql", dsnText)
	if nil != err {
		return 0, err
	}
	defer dbconn.Close()
	t0 := time.Now()
	for ; loopCount >= 0; loopCount-- {
		var result []byte
		if err = dbconn.QueryRow("SELECT NOW()").Scan(&result); nil != err {
			return 0, err
		}
		// fmt.Println("T:", result)
	}
	t1 := time.Now()
	return t1.Sub(t0), nil
}

func getLoopCount() (loopCount int) {
	loopCountText := os.Getenv("MNLOOPCNT")
	if len(loopCountText) > 0 {
		loopCount64, err := strconv.ParseInt(loopCountText, 0, 0)
		if (nil == err) && (loopCount64 > 0) {
			return int(loopCount64)
		}
	}
	return 10000000
}

func main() {
	if len(os.Args) < 2 {
		fmt.Println("export MNLOOPCNT=10000000")
		fmt.Println("user:password@tcp(127.0.0.1:3306)/MyDatabase")
		fmt.Println("user:password@unix(/tmp/mysql.sock)/MyDatabase")
		return
	}
	loopCount := getLoopCount()
	fmt.Println("loop:", loopCount)

	for _, dsnText := range os.Args[1:] {
		t0 := time.Now()
		queryLoopCost, err := runBench01Now(loopCount, dsnText)
		t1 := time.Now()
		totalCost := t1.Sub(t0)
		if nil != err {
			fmt.Println("ERR:", err)
		} else {
			fmt.Println(">", dsnText)
			fmt.Println("- query:", queryLoopCost, "total:", totalCost)
		}
	}
}