MySql 性能慢

I'm trying out performance of a system I'm building, and it's really slow, and I don't know why or if it should be this slow. What I'm testing is how many single INSERT I can do to the database and I get around 22 per second. That sounds really slow and when I tried to do the inserts i a singel big SQL-query I can insert 30000 records in about 0.5 seconds. In real life the inserts is made by different users in the system so the overhead of connecting, sending the query, parsing the query etc. will always be there. What I have tried so far:

• 用尽可能少的代码编写mysqli.= 每秒 22 次插入
• 使用尽可能少的代码的 PDO.= 每秒 22 次插入
• 将连接主机从本地主机更改为 127.0.0.1 = 每秒 22 次插入
• 没有语句对象的 mysqli 并检查 SQL 注入 = 每秒 22 次插入

所以这里似乎有问题.

系统规格:

• 英特尔 i5
• 16 公制内存
• 7200 rpm 磁盘驱动器

软件:

• Windows 10
• XAMPP，MariaDB 相当新
• 数据库引擎 innoDB.

我用来做测试的代码:

$amountToInsert = 1000;
//$fakeData is an array with randomly generated emails 
$fakeData = getFakeData($amountToInsert); 
$db = new DatabaseHandler();
for ($i = 0; $i < $amountToInsert; $i++) {
    $db->insertUser($fakeUsers[$i]);
}
$db->closeConnection();

调用数据库的类:

class DatabaseHandler {
    private $DBHOST = 'localhost';
    private $DBUSERNAME = 'username';
    private $DBPASSWORD = 'password';
    private $DBNAME = 'dbname';
    private $DBPORT = 3306;

    private $mDb;

    private $isConnected = false;

    public function __construct() {
        $this->mDb = new mysqli($this->DBHOST, $this->DBUSERNAME
                              , $this->DBPASSWORD, $this->DBNAME
                              , $this->DBPORT);
        $this->isConnected = true;
    }

    public function closeConnection() {
        if ($this->isConnected) {
            $threadId = $this->mDb->thread_id;
            $this->mDb->kill($threadId);
            $this->mDb->close();
            $this->isConnected = false;
        }
    }

    public function insertUser($user) {
        $this->mDb->autocommit(true);
        $queryString = 'INSERT INTO `users`(`email`, `company_id`) '
                        .'VALUES (?, 1)';
        $stmt = $this->mDb->prepare($queryString);
        $stmt->bind_param('s', $user);
        if ($stmt->execute()) {
            $stmt->close();
            return 1;
        } else {
            $stmt->close();
            return 0;
        }
    }
}

user"表有 4 列，结构如下:

innodb_flush_log_at_trx_commit = 0