PDOException: SQLSTATE[HY000] [1040] Too many connections in /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php:128
Stack trace:
#0 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php(128): PDO->__construct()
#1 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Mysql.php(111): Zend_Db_Adapter_Pdo_Abstract->_connect()
#2 /var/www/html/magento2/lib/internal/Magento/Framework/DB/Adapter/Pdo/Mysql.php(413): Zend_Db_Adapter_Pdo_Mysql->_connect()
#3 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Abstract.php(460): Magento\Framework\DB\Adapter\Pdo\Mysql->_connect()
#4 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php(238): Zend_Db_Adapter_Abstract->query()
#5 /var/www/html/magento2/lib/internal/Magento/Framework/DB/Adapter/Pdo/Mysql.php(549): Zend_Db_Adapter_Pdo_Abstract->query()
#6 /var/www/html/magento2/lib/internal/Magento/Framework/DB/Adapter/Pdo/Mysql.php(616): Magento\Framework\DB\Adapter\Pdo\Mysql->_query()
#7 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Abstract.php(737): Magento\Framework\DB\Adapter\Pdo\Mysql->query()
#8 /var/www/html/magento2/app/code/Magento/Store/App/Config/Source/RuntimeConfigSource.php(101): Zend_Db_Adapter_Abstract->fetchAll()
#9 /var/www/html/magento2/app/code/Magento/Store/App/Config/Source/RuntimeConfigSource.php(61): Magento\Store\App\Config\Source\RuntimeConfigSource->getEntities()
#10 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config/ConfigSourceAggregated.php(40): Magento\Store\App\Config\Source\RuntimeConfigSource->get()
#11 /var/www/html/magento2/generated/code/Magento/Framework/App/Config/ConfigSourceAggregated/Proxy.php(95): Magento\Framework\App\Config\ConfigSourceAggregated->get()
#12 /var/www/html/magento2/app/code/Magento/Store/App/Config/Type/Scopes.php(63): Magento\Framework\App\Config\ConfigSourceAggregated\Proxy->get()
#13 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config.php(132): Magento\Store\App\Config\Type\Scopes->get()
#14 /var/www/html/magento2/app/code/Magento/Store/Model/StoreRepository.php(106): Magento\Framework\App\Config->get()
#15 /var/www/html/magento2/app/code/Magento/Store/Model/StoreRepository.php(127): Magento\Store\Model\StoreRepository->getById()
#16 /var/www/html/magento2/app/code/Magento/Store/Model/StoreResolver.php(181): Magento\Store\Model\StoreRepository->getActiveStoreById()
#17 /var/www/html/magento2/app/code/Magento/Store/Model/StoreResolver.php(126): Magento\Store\Model\StoreResolver->getDefaultStoreById()
#18 /var/www/html/magento2/app/code/Magento/Store/Model/StoreManager.php(160): Magento\Store\Model\StoreResolver->getCurrentStoreId()
#19 /var/www/html/magento2/generated/code/Magento/Store/Model/StoreManagerInterface/Proxy.php(119): Magento\Store\Model\StoreManager->getStore()
#20 /var/www/html/magento2/app/code/Magento/Store/Model/Resolver/Store.php(30): Magento\Store\Model\StoreManagerInterface\Proxy->getStore()
#21 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config/ScopeCodeResolver.php(49): Magento\Store\Model\Resolver\Store->getScope()
#22 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config.php(69): Magento\Framework\App\Config\ScopeCodeResolver->resolve()
#23 /var/www/html/magento2/generated/code/Magento/Framework/App/Config/Interceptor.php(24): Magento\Framework\App\Config->getValue()
#24 /var/www/html/magento2/lib/internal/Magento/Framework/Session/Config.php(195): Magento\Framework\App\Config\Interceptor->getValue()
#25 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/AbstractFactory.php(121): Magento\Framework\Session\Config->__construct()
#26 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(108): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject()
#27 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/ObjectManager.php(70): Magento\Framework\ObjectManager\Factory\Compiled->create()
#28 /var/www/html/magento2/lib/internal/Magento/Framework/App/Response/Http.php(85): Magento\Framework\ObjectManager\ObjectManager->get()
#29 /var/www/html/magento2/app/code/Magento/MediaStorage/Model/File/Storage/Response.php(47): Magento\Framework\App\Response\Http->__construct()
#30 /var/www/html/magento2/generated/code/Magento/MediaStorage/Model/File/Storage/Response/Interceptor.php(14): Magento\MediaStorage\Model\File\Storage\Response->__construct()
#31 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/AbstractFactory.php(121): Magento\MediaStorage\Model\File\Storage\Response\Interceptor->__construct()
#32 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(108): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject()
#33 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(150): Magento\Framework\ObjectManager\Factory\Compiled->create()
#34 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(79): Magento\Framework\ObjectManager\Factory\Compiled->get()
#35 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/ObjectManager.php(56): Magento\Framework\ObjectManager\Factory\Compiled->create()
#36 /var/www/html/magento2/lib/internal/Magento/Framework/App/Bootstrap.php(235): Magento\Framework\ObjectManager\ObjectManager->create()
#37 /var/www/html/magento2/pub/get.php(81): Magento\Framework\App\Bootstrap->createApplication()
#38 {main}

Next Zend_Db_Adapter_Exception: SQLSTATE[HY000] [1040] Too many connections in /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php:144
Stack trace:
#0 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Mysql.php(111): Zend_Db_Adapter_Pdo_Abstract->_connect()
#1 /var/www/html/magento2/lib/internal/Magento/Framework/DB/Adapter/Pdo/Mysql.php(413): Zend_Db_Adapter_Pdo_Mysql->_connect()
#2 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Abstract.php(460): Magento\Framework\DB\Adapter\Pdo\Mysql->_connect()
#3 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php(238): Zend_Db_Adapter_Abstract->query()
#4 /var/www/html/magento2/lib/internal/Magento/Framework/DB/Adapter/Pdo/Mysql.php(549): Zend_Db_Adapter_Pdo_Abstract->query()
#5 /var/www/html/magento2/lib/internal/Magento/Framework/DB/Adapter/Pdo/Mysql.php(616): Magento\Framework\DB\Adapter\Pdo\Mysql->_query()
#6 /var/www/html/magento2/vendor/magento/zendframework1/library/Zend/Db/Adapter/Abstract.php(737): Magento\Framework\DB\Adapter\Pdo\Mysql->query()
#7 /var/www/html/magento2/app/code/Magento/Store/App/Config/Source/RuntimeConfigSource.php(101): Zend_Db_Adapter_Abstract->fetchAll()
#8 /var/www/html/magento2/app/code/Magento/Store/App/Config/Source/RuntimeConfigSource.php(61): Magento\Store\App\Config\Source\RuntimeConfigSource->getEntities()
#9 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config/ConfigSourceAggregated.php(40): Magento\Store\App\Config\Source\RuntimeConfigSource->get()
#10 /var/www/html/magento2/generated/code/Magento/Framework/App/Config/ConfigSourceAggregated/Proxy.php(95): Magento\Framework\App\Config\ConfigSourceAggregated->get()
#11 /var/www/html/magento2/app/code/Magento/Store/App/Config/Type/Scopes.php(63): Magento\Framework\App\Config\ConfigSourceAggregated\Proxy->get()
#12 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config.php(132): Magento\Store\App\Config\Type\Scopes->get()
#13 /var/www/html/magento2/app/code/Magento/Store/Model/StoreRepository.php(106): Magento\Framework\App\Config->get()
#14 /var/www/html/magento2/app/code/Magento/Store/Model/StoreRepository.php(127): Magento\Store\Model\StoreRepository->getById()
#15 /var/www/html/magento2/app/code/Magento/Store/Model/StoreResolver.php(181): Magento\Store\Model\StoreRepository->getActiveStoreById()
#16 /var/www/html/magento2/app/code/Magento/Store/Model/StoreResolver.php(126): Magento\Store\Model\StoreResolver->getDefaultStoreById()
#17 /var/www/html/magento2/app/code/Magento/Store/Model/StoreManager.php(160): Magento\Store\Model\StoreResolver->getCurrentStoreId()
#18 /var/www/html/magento2/generated/code/Magento/Store/Model/StoreManagerInterface/Proxy.php(119): Magento\Store\Model\StoreManager->getStore()
#19 /var/www/html/magento2/app/code/Magento/Store/Model/Resolver/Store.php(30): Magento\Store\Model\StoreManagerInterface\Proxy->getStore()
#20 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config/ScopeCodeResolver.php(49): Magento\Store\Model\Resolver\Store->getScope()
#21 /var/www/html/magento2/lib/internal/Magento/Framework/App/Config.php(69): Magento\Framework\App\Config\ScopeCodeResolver->resolve()
#22 /var/www/html/magento2/generated/code/Magento/Framework/App/Config/Interceptor.php(24): Magento\Framework\App\Config->getValue()
#23 /var/www/html/magento2/lib/internal/Magento/Framework/Session/Config.php(195): Magento\Framework\App\Config\Interceptor->getValue()
#24 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/AbstractFactory.php(121): Magento\Framework\Session\Config->__construct()
#25 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(108): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject()
#26 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/ObjectManager.php(70): Magento\Framework\ObjectManager\Factory\Compiled->create()
#27 /var/www/html/magento2/lib/internal/Magento/Framework/App/Response/Http.php(85): Magento\Framework\ObjectManager\ObjectManager->get()
#28 /var/www/html/magento2/app/code/Magento/MediaStorage/Model/File/Storage/Response.php(47): Magento\Framework\App\Response\Http->__construct()
#29 /var/www/html/magento2/generated/code/Magento/MediaStorage/Model/File/Storage/Response/Interceptor.php(14): Magento\MediaStorage\Model\File\Storage\Response->__construct()
#30 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/AbstractFactory.php(121): Magento\MediaStorage\Model\File\Storage\Response\Interceptor->__construct()
#31 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(108): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject()
#32 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(150): Magento\Framework\ObjectManager\Factory\Compiled->create()
#33 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Compiled.php(79): Magento\Framework\ObjectManager\Factory\Compiled->get()
#34 /var/www/html/magento2/lib/internal/Magento/Framework/ObjectManager/ObjectManager.php(56): Magento\Framework\ObjectManager\Factory\Compiled->create()
#35 /var/www/html/magento2/lib/internal/Magento/Framework/App/Bootstrap.php(235): Magento\Framework\ObjectManager\ObjectManager->create()
#36 /var/www/html/magento2/pub/get.php(81): Magento\Framework\App\Bootstrap->createApplication()
#37 {main}