diff --git a/DatabasesProviders.php b/DatabasesProviders.php
index 376193b..cfd20d5 100644
--- a/DatabasesProviders.php
+++ b/DatabasesProviders.php
@@ -47,8 +47,6 @@ class DatabasesProviders extends Providers
 		if (empty($databases)) {
 			return;
 		}
-		$this->provider->on(OnWorkerStart::class, [$this, 'check']);
-		$this->provider->on(OnTaskerStart::class, [$this, 'check']);
 		$this->provider->on(OnWorkerExit::class, [$this, 'exit'], 9999);
 		foreach ($databases as $key => $database) {
 			$application->set($key, $this->_settings($database));
@@ -85,61 +83,6 @@ class DatabasesProviders extends Providers
 	}
 
 
-	/**
-	 * @param OnTaskerStart|OnWorkerStart $start
-	 * @return void
-	 */
-	public function check(OnTaskerStart|OnWorkerStart $start): void
-	{
-		Timer::tick(10000, function ($timerId) {
-			$valid = $count = 0;
-			$logger = Kiri::getDi()->get(LoggerInterface::class);
-			$databases = Config::get('databases.connections', []);
-			if (!empty($databases)) {
-				[$valid, $count] = $this->each($databases, $logger);
-			}
-			$const = 'Worker %d db client has %d, valid %d';
-			$logger->alert(sprintf($const, env('environmental_workerId'), $count, $valid));
-			if ($this->container->get(WorkerStatus::class)->is(StatusEnum::EXIT)) {
-				Timer::clear($timerId);
-			}
-		});
-	}
-
-
-	/**
-	 * @param $databases
-	 * @param LoggerInterface $logger
-	 * @return array
-	 */
-	public function each($databases, LoggerInterface $logger): array
-	{
-		$connection = Kiri::getDi()->get(PoolConnection::class);
-		$valid = $count = 0;
-		foreach ($databases as $database) {
-			try {
-				[$total, $success] = $connection->check($database['cds']);
-
-				$count += $total;
-				$valid += $success;
-
-				if (isset($database['slaveConfig']) && isset($database['slaveConfig']['cds'])) {
-					if ($database['slaveConfig']['cds'] != $database['cds']) {
-						[$total, $success] = $connection->check($database['slaveConfig']['cds']);
-
-						$count += $total;
-						$valid += $success;
-					}
-				}
-			} catch (\Throwable $throwable) {
-				$logger->error($throwable->getMessage());
-			}
-		}
-
-		return [$valid, $count];
-	}
-
-
 	/**
 	 * @param $database
 	 * @return array
diff --git a/Mysql/PDO.php b/Mysql/PDO.php
index fd3e9ad..43a98b1 100644
--- a/Mysql/PDO.php
+++ b/Mysql/PDO.php
@@ -8,6 +8,9 @@ use Kiri\Events\EventProvider;
 use Kiri\Pool\StopHeartbeatCheck;
 use Kiri\Server\Events\OnWorkerExit;
 use PDOStatement;
+use Kiri\Server\WorkerStatus;
+use Kiri\Server\Abstracts\StatusEnum;
+use Swoole\Timer;
 
 /**
  *
@@ -15,308 +18,334 @@ use PDOStatement;
 class PDO implements StopHeartbeatCheck
 {
 
-	const DB_ERROR_MESSAGE = 'The system is busy, please try again later.';
+    const DB_ERROR_MESSAGE = 'The system is busy, please try again later.';
 
 
-	private ?\PDO $pdo = null;
+    private ?\PDO $pdo = null;
 
 
-	private int $_transaction = 0;
+    private int $_transaction = 0;
 
-	private int $_last = 0;
+    private int $_last = 0;
 
-	public string $dbname;
-	public string $cds;
-	public string $username;
-	public string $password;
-	public string $charset;
-	public int $connect_timeout;
-	public int $read_timeout;
+    public string $dbname;
+    public string $cds;
+    public string $username;
+    public string $password;
+    public string $charset;
+    public int $connect_timeout;
+    public int $read_timeout;
+
+    private int $_timerId = -1;
 
 
-	public array $attributes = [];
+    public array $attributes = [];
 
 
-	/**
-	 * @param array $config
-	 */
-	public function __construct(array $config)
-	{
-		$this->dbname = $config['dbname'];
-		$this->cds = $config['cds'];
-		$this->username = $config['username'];
-		$this->password = $config['password'];
-		$this->connect_timeout = $config['connect_timeout'] ?? 30;
-		$this->read_timeout = $config['read_timeout'] ?? 10;
-		$this->charset = $config['charset'] ?? 'utf8mb4';
-		$this->attributes = $config['attributes'] ?? [];
-	}
+    /**
+     * @param array $config
+     */
+    public function __construct(array $config)
+    {
+        $this->dbname = $config['dbname'];
+        $this->cds = $config['cds'];
+        $this->username = $config['username'];
+        $this->password = $config['password'];
+        $this->connect_timeout = $config['connect_timeout'] ?? 30;
+        $this->read_timeout = $config['read_timeout'] ?? 10;
+        $this->charset = $config['charset'] ?? 'utf8mb4';
+        $this->attributes = $config['attributes'] ?? [];
+    }
 
 
-	/**
-	 * @return void
-	 * @throws Exception
-	 */
-	public function init(): void
-	{
-		$eventProvider = Kiri::getDi()->get(EventProvider::class);
-		$eventProvider->on(OnWorkerExit::class, [$this, 'onWorkerExit']);
-	}
+    /**
+     * @return void
+     * @throws Exception
+     */
+    public function init(): void
+    {
+        $eventProvider = Kiri::getDi()->get(EventProvider::class);
+        $eventProvider->on(OnWorkerExit::class, [$this, 'onWorkerExit']);
+        $this->_timerId = Timer::tick(60000, [$this, 'check']);
+    }
 
 
-	/**
-	 * @return bool
-	 */
-	public function inTransaction(): bool
-	{
-		return $this->_transaction > 0;
-	}
+    /**
+     * @return bool
+     */
+    public function inTransaction(): bool
+    {
+        return $this->_transaction > 0;
+    }
 
 
-	/**
-	 * @param Kiri\Server\Events\OnWorkerExit $exit
-	 * @return void
-	 */
-	public function onWorkerExit(OnWorkerExit $exit): void
-	{
-		$this->stopHeartbeatCheck();
-	}
+    /**
+     * @param Kiri\Server\Events\OnWorkerExit $exit
+     * @return void
+     */
+    public function onWorkerExit(OnWorkerExit $exit): void
+    {
+        $this->stopHeartbeatCheck();
+    }
 
 
-	/**
-	 *
-	 */
-	public function stopHeartbeatCheck(): void
-	{
-		$this->pdo = null;
-	}
+    /**
+     *
+     */
+    public function stopHeartbeatCheck(): void
+    {
+        $this->pdo = null;
+        if ($this->_timerId > -1) {
+            Timer::clear($this->_timerId);
+            $this->_timerId = -1;
+        }
+    }
 
 
-	/**
-	 *
-	 */
-	public function beginTransaction()
-	{
-		if ($this->_transaction == 0) {
-			$this->_pdo()->beginTransaction();
-		}
-		$this->_transaction++;
-	}
+    /**
+     *
+     */
+    public function beginTransaction()
+    {
+        if ($this->_transaction == 0) {
+            $this->_pdo()->beginTransaction();
+        }
+        $this->_transaction++;
+    }
 
 
-	/**
-	 *
-	 */
-	public function commit()
-	{
-		$this->_transaction--;
-		if ($this->_transaction == 0) {
-			$this->_pdo()->commit();
-		}
-	}
+    /**
+     *
+     */
+    public function commit()
+    {
+        $this->_transaction--;
+        if ($this->_transaction == 0) {
+            $this->_pdo()->commit();
+        }
+    }
 
 
-	/**
-	 *
-	 */
-	public function rollback()
-	{
-		$this->_transaction--;
-		if ($this->_transaction == 0) {
-			$this->_pdo()->rollBack();
-		}
-	}
+    /**
+     *
+     */
+    public function rollback()
+    {
+        $this->_transaction--;
+        if ($this->_transaction == 0) {
+            $this->_pdo()->rollBack();
+        }
+    }
 
 
-	/**
-	 * @param string $sql
-	 * @param array $params
-	 * @return bool|array|null
-	 * @throws Exception
-	 */
-	public function fetchAll(string $sql, array $params = []): bool|null|array
-	{
-		$pdo = $this->queryPrev($sql, $params);
+    /**
+     * @param string $sql
+     * @param array $params
+     * @return bool|array|null
+     * @throws Exception
+     */
+    public function fetchAll(string $sql, array $params = []): bool|null|array
+    {
+        $pdo = $this->queryPrev($sql, $params);
 
-		$result = $pdo->fetchAll(\PDO::FETCH_ASSOC);
-		$pdo->closeCursor();
-		return $result;
-	}
+        $result = $pdo->fetchAll(\PDO::FETCH_ASSOC);
+        $pdo->closeCursor();
+        return $result;
+    }
 
 
-	/**
-	 * @param string $sql
-	 * @param array $params
-	 * @return bool|array|null
-	 * @throws Exception
-	 */
-	public function fetch(string $sql, array $params = []): bool|null|array
-	{
-		$pdo = $this->queryPrev($sql, $params);
+    /**
+     * @param string $sql
+     * @param array $params
+     * @return bool|array|null
+     * @throws Exception
+     */
+    public function fetch(string $sql, array $params = []): bool|null|array
+    {
+        $pdo = $this->queryPrev($sql, $params);
 
-		$result = $pdo->fetch(\PDO::FETCH_ASSOC);
-		$pdo->closeCursor();
-		return $result;
-	}
+        $result = $pdo->fetch(\PDO::FETCH_ASSOC);
+        $pdo->closeCursor();
+        return $result;
+    }
 
 
-	/**
-	 * @param string $sql
-	 * @param array $params
-	 * @return bool|array|null
-	 * @throws \Exception
-	 */
-	public function fetchColumn(string $sql, array $params = []): bool|null|array
-	{
-		$pdo = $this->queryPrev($sql, $params);
+    /**
+     * @param string $sql
+     * @param array $params
+     * @return bool|array|null
+     * @throws \Exception
+     */
+    public function fetchColumn(string $sql, array $params = []): bool|null|array
+    {
+        $pdo = $this->queryPrev($sql, $params);
 
-		$result = $pdo->fetchColumn(\PDO::FETCH_ASSOC);
-		$pdo->closeCursor();
-		return $result;
-	}
+        $result = $pdo->fetchColumn(\PDO::FETCH_ASSOC);
+        $pdo->closeCursor();
+        return $result;
+    }
 
 
-	/**
-	 * @param string $sql
-	 * @param array $params
-	 * @return int
-	 * @throws Exception
-	 */
-	public function count(string $sql, array $params = []): int
-	{
-		$pdo = $this->queryPrev($sql, $params);
+    /**
+     * @param string $sql
+     * @param array $params
+     * @return int
+     * @throws Exception
+     */
+    public function count(string $sql, array $params = []): int
+    {
+        $pdo = $this->queryPrev($sql, $params);
 
-		$result = $pdo->rowCount();
-		$pdo->closeCursor();
-		return $result;
-	}
+        $result = $pdo->rowCount();
+        $pdo->closeCursor();
+        return $result;
+    }
 
 
-	/**
-	 * @param string $sql
-	 * @param array $params
-	 * @return PDOStatement
-	 * @throws Exception
-	 */
-	private function queryPrev(string $sql, array $params = []): PDOStatement
-	{
-		$this->_last = time();
-		try {
-			if (($statement = $this->_pdo()->query($sql)) === false) {
-				throw new Exception($this->_pdo()->errorInfo()[1]);
-			}
-			return $this->bindValue($statement, $params);
-		} catch (\PDOException|\Throwable $throwable) {
-			if (str_contains($throwable->getMessage(), 'MySQL server has gone away')) {
-				$this->pdo = null;
+    /**
+     * @param string $sql
+     * @param array $params
+     * @return PDOStatement
+     * @throws Exception
+     */
+    private function queryPrev(string $sql, array $params = []): PDOStatement
+    {
+        try {
+            if ($this->_timerId === -1) {
+                $this->_timerId = Timer::tick(6000, [$this, 'check']);
+            }
+            $this->_last = time();
+            if (($statement = $this->_pdo()->query($sql)) === false) {
+                throw new Exception($this->_pdo()->errorInfo()[1]);
+            }
+            return $this->bindValue($statement, $params);
+        } catch (\PDOException|\Throwable $throwable) {
+            if (str_contains($throwable->getMessage(), 'MySQL server has gone away')) {
+                $this->pdo = null;
 
-				return $this->queryPrev($sql, $params);
-			}
-			throw new Exception($throwable->getMessage());
-		}
-	}
+                return $this->queryPrev($sql, $params);
+            }
+            throw new Exception($throwable->getMessage());
+        }
+    }
 
 
-	/**
-	 * @return bool
-	 */
-	public function check(): bool
-	{
-		try {
-			if ($this->_last == 0) $this->_last = time();
-			if (time() - $this->_last >= 600) {
-				throw new Exception('Idle dis.');
-			}
-			if (!($this->pdo instanceof \PDO)) {
-				return $result = false;
-			}
-			$this->pdo->getAttribute(\PDO::ATTR_SERVER_INFO);
-			$result = true;
-		} catch (\Throwable $throwable) {
-			if (!str_contains($throwable->getMessage(), 'Idle dis')) {
-				Kiri::getLogger()->error($throwable->getMessage());
-			}
-			$this->pdo = null;
-			$result = false;
-		} finally {
-			return $result;
-		}
-	}
+    /**
+     * @return bool
+     */
+    public function check(): bool
+    {
+        try {
+            if ($this->_last == 0) $this->_last = time();
+            if (time() - $this->_last >= 600) {
+                return $result = false;
+            } else if (!($this->pdo instanceof \PDO)) {
+                return $result = false;
+            }
+            $this->pdo->getAttribute(\PDO::ATTR_SERVER_INFO);
+            $result = true;
+        } catch (\Throwable $throwable) {
+            if (!str_contains($throwable->getMessage(), 'Idle dis')) {
+                Kiri::getLogger()->error($throwable->getMessage());
+            }
+            $result = false;
+        } finally {
+            return $this->afterCheck($result);
+        }
+    }
 
 
-	/**
-	 * @param PDOStatement $statement
-	 * @param array $params
-	 * @return PDOStatement
-	 */
-	private function bindValue(PDOStatement $statement, array $params = []): PDOStatement
-	{
-		if (empty($params)) return $statement;
-		foreach ($params as $key => $param) {
-			$statement->bindValue($key, $param);
-		}
-		return $statement;
-	}
+    /**
+     * @param bool $result
+     * @return bool
+     */
+    private function afterCheck(bool $result): bool
+    {
+        $container = Kiri::getDi()->get(WorkerStatus::class);
+        if (!$result || $container->is(StatusEnum::EXIT)) {
+            $this->pdo = null;
+            $result = Timer::clear($this->_timerId);
+            $this->_timerId = -1;
+        }
+        return $result;
+    }
 
 
-	/**
-	 * @param string $sql
-	 * @param array $params
-	 * @return int
-	 * @throws Exception
-	 */
-	public function execute(string $sql, array $params = []): int
-	{
-		$this->_last = time();
-		$pdo = $this->_pdo();
-		if (!(($prepare = $pdo->prepare($sql)) instanceof PDOStatement)) {
-			throw new Exception($prepare->errorInfo()[2] ?? static::DB_ERROR_MESSAGE);
-		}
-		if ($prepare->execute($params) === false) {
-			throw new Exception($prepare->errorInfo()[2] ?? static::DB_ERROR_MESSAGE);
-		}
-		$result = (int)$pdo->lastInsertId();
-		$prepare->closeCursor();
-		if ($result == 0) {
-			return true;
-		}
-		return $result;
-	}
+    /**
+     * @param PDOStatement $statement
+     * @param array $params
+     * @return PDOStatement
+     */
+    private function bindValue(PDOStatement $statement, array $params = []): PDOStatement
+    {
+        if (empty($params)) return $statement;
+        foreach ($params as $key => $param) {
+            $statement->bindValue($key, $param);
+        }
+        return $statement;
+    }
 
 
-	/**
-	 * @return \PDO
-	 */
-	public function _pdo(): \PDO
-	{
-		if (!($this->pdo instanceof \PDO)) {
-			$this->pdo = $this->newClient();
-		}
-		return $this->pdo;
-	}
+    /**
+     * @param string $sql
+     * @param array $params
+     * @return int
+     * @throws Exception
+     */
+    public function execute(string $sql, array $params = []): int
+    {
+        $pdo = $this->_pdo();
+        if ($this->_timerId === -1) {
+            $this->_timerId = Timer::tick(6000, [$this, 'check']);
+        }
+        $this->_last = time();
+        if (!(($prepare = $pdo->prepare($sql)) instanceof PDOStatement)) {
+            throw new Exception($prepare->errorInfo()[2] ?? static::DB_ERROR_MESSAGE);
+        }
+        if ($prepare->execute($params) === false) {
+            throw new Exception($prepare->errorInfo()[2] ?? static::DB_ERROR_MESSAGE);
+        }
+
+        $result = (int)$pdo->lastInsertId();
+        $prepare->closeCursor();
+
+        return $result == 0 ? true : $result;
+    }
 
 
-	/**
-	 * @return \PDO
-	 */
-	private function newClient(): \PDO
-	{
-		$link = new \PDO('mysql:dbname=' . $this->dbname . ';host=' . $this->cds, $this->username, $this->password, [
-			\PDO::ATTR_EMULATE_PREPARES         => false,
-			\PDO::ATTR_CASE                     => \PDO::CASE_NATURAL,
-			\PDO::ATTR_TIMEOUT                  => $this->connect_timeout,
-			\PDO::MYSQL_ATTR_USE_BUFFERED_QUERY => true,
-			\PDO::MYSQL_ATTR_INIT_COMMAND       => 'SET NAMES ' . $this->charset
-		]);
-		$link->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
-		$link->setAttribute(\PDO::ATTR_STRINGIFY_FETCHES, false);
-		$link->setAttribute(\PDO::ATTR_ORACLE_NULLS, \PDO::NULL_EMPTY_STRING);
-		if (!empty($this->attributes)) {
-			foreach ($this->attributes as $key => $attribute) {
-				$link->setAttribute($key, $attribute);
-			}
-		}
-		return $link;
-	}
+    /**
+     * @return \PDO
+     */
+    public function _pdo(): \PDO
+    {
+        if (!($this->pdo instanceof \PDO)) {
+            $this->pdo = $this->newClient();
+        }
+        return $this->pdo;
+    }
+
+
+    /**
+     * @return \PDO
+     */
+    private function newClient(): \PDO
+    {
+        $link = new \PDO('mysql:dbname=' . $this->dbname . ';host=' . $this->cds, $this->username, $this->password, [
+            \PDO::ATTR_EMULATE_PREPARES => false,
+            \PDO::ATTR_CASE => \PDO::CASE_NATURAL,
+            \PDO::ATTR_TIMEOUT => $this->connect_timeout,
+            \PDO::MYSQL_ATTR_USE_BUFFERED_QUERY => true,
+            \PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES ' . $this->charset
+        ]);
+        $link->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
+        $link->setAttribute(\PDO::ATTR_STRINGIFY_FETCHES, false);
+        $link->setAttribute(\PDO::ATTR_ORACLE_NULLS, \PDO::NULL_EMPTY_STRING);
+        if (!empty($this->attributes)) {
+            foreach ($this->attributes as $key => $attribute) {
+                $link->setAttribute($key, $attribute);
+            }
+        }
+        return $link;
+    }
 
 }