added concurrent query util

go/utils/concurrency/runner.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"os"
+
+	_ "github.com/go-sql-driver/mysql"
+	"golang.org/x/sync/errgroup"
+)
+
+const clients = 16
+
+var sqlScript = []string{
+	"call dolt_checkout('main');",
+	"select * from dolt_log order by date desc limit 10;",
+}
+
+var (
+	database = "SHAQ"
+	user     = "root"
+	pass     = ""
+	host     = "127.0.0.1"
+	port     = "3306"
+)
+
+func main() {
+	connStr := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s",
+		user, pass, host, port, database)
+
+	db, err := sql.Open("mysql", connStr)
+	maybeExit(err)
+
+	eg, ctx := errgroup.WithContext(context.Background())
+
+	for i := 0; i < clients; i++ {
+		eg.Go(func() (err error) {
+			conn, err := db.Conn(ctx)
+			if err != nil {
+				return err
+			}
+			defer func() {
+				cerr := conn.Close()
+				if err != nil {
+					err = cerr
+				}
+			}()
+			for j := 0; j < 10; j++ {
+				if err = query(ctx, conn); err != nil {
+					return err
+				}
+			}
+			return
+		})
+	}
+	maybeExit(eg.Wait())
+}
+
+func query(ctx context.Context, conn *sql.Conn) error {
+	for i := range sqlScript {
+		_, err := conn.ExecContext(ctx, sqlScript[i])
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func maybeExit(err error) {
+	if err != nil {
+		fmt.Println(err.Error())
+		os.Exit(1)
+	}
+}