我正在使用AWS SES客户端批量发送电子邮件，但过了一段时间后我收到以下错误：
PHP Fatal error: Uncaught exception Guzzle\Service\Exception\CommandTransferException' with message 'Errors during multi transfer
(Guzzle\Http\Exception\CurlException) /var/www/vhosts/domain.com/vendor/guzzle/guzzle/src/Guzzle/Http/Curl/CurlMulti.php line 359
[curl] 35: error:02001018:system library:fopen:Too many open files [url] https://email.us-east-1.amazonaws.com/
#0 /var/www/vhosts/domain.com/vendor/guzzle/guzzle/src/Guzzle/Http/Curl/CurlMulti.php(292): Guzzle\Http\Curl\CurlMulti->isCurlException(Object(Guzzle\Http\Message\EntityEnclosingRequest), Object(Guzzle\Http\Curl\CurlHandle), Array)
#1 /var/www/vhosts/domain.com/vendor/guzzle/guzzle/src/Guzzle/Http/Curl/CurlMulti.php(257): Guzzle\Http\Curl\CurlMulti->processResponse(Object(Guzzle\Http\Message\EntityEnclosingRequest), Object(Guzzle\Http\Curl\CurlHandle), Array)
#2 /var/www/vhosts/domain.com/vendor/guzzle/guzzle/src/Guzzle/Http/Curl/CurlMulti.php(240): Guzzle\Http\Curl\CurlMulti->processMessages()
#3 /var/www/vhos in /var/www/vhosts/domain.com/vendor/guzzle/guzzle/src/Guzzle/Batch/Batch.php on line 62