diff --git a/Connection.php b/Connection.php
index 1dc52d3..4099899 100644
--- a/Connection.php
+++ b/Connection.php
@@ -26,11 +26,13 @@ use Kiri\Events\EventProvider;
 use Kiri\Exception\NotFindClassException;
 use PDO;
 use Kiri\Error\StdoutLogger;
-use PDOStatement;
 use Psr\Log\LoggerInterface;
 use ReflectionException;
+use Kiri\Server\Events\OnWorkerStart;
+use Kiri\Server\Events\OnTaskerStart;
 use Kiri\Server\Events\OnAfterRequest;
 use Kiri\Di\Inject\Container;
+use Swoole\Timer;
 
 /**
  * Class Connection
@@ -39,11 +41,11 @@ use Kiri\Di\Inject\Container;
 class Connection extends Component
 {
 
-    public string $id       = 'db';
-    public string $cds      = '';
+    public string $id = 'db';
+    public string $cds = '';
     public string $password = '';
     public string $username = '';
-    public string $charset  = 'utf-8';
+    public string $charset = 'utf-8';
 
     public string $tablePrefix = '';
 
@@ -115,6 +117,48 @@ class Connection extends Component
         $eventProvider->on(Commit::class, [$this, 'commit'], 0);
         $eventProvider->on(OnAfterRequest::class, [$this, 'clear']);
         $eventProvider->on(OnWorkerExit::class, [$this, 'disconnect']);
+        $eventProvider->on(OnWorkerStart::class, [$this, 'tick']);
+        $eventProvider->on(OnTaskerStart::class, [$this, 'tick']);
+    }
+
+
+    /**
+     * @return void
+     */
+    public function tick(): void
+    {
+        Timer::tick(10000, fn() => $this->checkClientHealth($this->pool()));
+    }
+
+
+    /**
+     * @param Pool $pool
+     * @return void
+     * @throws Exception
+     */
+    protected function checkClientHealth(Pool $pool): void
+    {
+        $length = $pool->size($this->cds);
+        for ($i = 0; $i < $length; $i++) {
+            try {
+                $bool = $pool->get($this->cds);
+                if ($bool === false) {
+                    break;
+                }
+                /** @var PDO $client */
+                [$client, $time] = $bool;
+                if ((time() - $time) > $this->idle_time) {
+                    throw new Exception('Client timeout.');
+                }
+                if ($client->query('select 1') === false) {
+                    throw new Exception($client->errorInfo()[1]);
+                }
+                $pool->push($this->cds, [$client, time()]);
+            } catch (\Throwable $exception) {
+                $this->logger->error(throwable($exception));
+                $pool->abandon($this->cds);
+            }
+        }
     }
 
 
@@ -129,7 +173,7 @@ class Connection extends Component
         if ($this->_schema === null) {
             $this->_schema = Kiri::createObject([
                 'class' => Schema::class,
-                'db'    => $this
+                'db' => $this
             ]);
         }
         return $this->_schema;
@@ -162,14 +206,13 @@ class Connection extends Component
         }
 
         [$client, $time] = $data;
-        if ((time() - $time) < $this->idle_time && $this->canUse($client)) {
+        if ((time() - $time) < $this->idle_time) {
             return $client;
         }
 
         $this->logger->error('PDO连接已失效, 空闲超时或已不可用，重新获取.', [$this->cds]);
         $this->pool()->abandon($this->cds);
 
-        Waite::sleep(10);
         return $this->getNormalClientHealth();
     }
 
@@ -256,7 +299,7 @@ class Connection extends Component
             if ($pdo === null) {
                 throw new Exception('Failed to rollback transaction: connection was exists.');
             }
-            if ($this->inTransaction()) {
+            if ($pdo->inTransaction()) {
                 $pdo->rollback();
             }
             $this->pool()->push($this->cds, [$pdo, time()]);
@@ -350,28 +393,27 @@ class Connection extends Component
 
 
     /**
-     * @return array
+     * @return array<PDO, int>
      */
     public function newConnect(): array
     {
-        $options = array_merge($this->attributes, [
-            PDO::ATTR_CASE               => PDO::CASE_NATURAL,
-            PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
-            PDO::ATTR_ORACLE_NULLS       => PDO::NULL_NATURAL,
-            PDO::ATTR_STRINGIFY_FETCHES  => false,
-            PDO::ATTR_EMULATE_PREPARES   => true,
-            PDO::ATTR_TIMEOUT            => $this->connect_timeout,
-            PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES ' . $this->charset
-        ]);
-        $link = new PDO('mysql:dbname=' . $this->database . ';host=' . $this->cds, $this->username, $this->password, $options);
-        return [$link, time()];
+        return [new PDO('mysql:dbname=' . $this->database . ';host=' . $this->cds,
+            $this->username, $this->password, array_merge($this->attributes, [
+                PDO::ATTR_CASE => PDO::CASE_NATURAL,
+                PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
+                PDO::ATTR_ORACLE_NULLS => PDO::NULL_NATURAL,
+                PDO::ATTR_STRINGIFY_FETCHES => false,
+                PDO::ATTR_EMULATE_PREPARES => true,
+                PDO::ATTR_TIMEOUT => $this->connect_timeout,
+                PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES ' . $this->charset
+            ])), time()];
     }
 
 
     /**
      * @return Pool
      */
-    private function pool(): Pool
+    protected function pool(): Pool
     {
         if (!$this->connections->hasChannel($this->cds)) {
             $this->connections->created($this->cds, $this->pool['max'] ?? 1, [$this, 'newConnect']);