Uncaught exception thrown in shutdown function.

Drupal\Core\Database\DatabaseExceptionWrapper: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away: CREATE TABLE {cache_default} ( `cid` VARCHAR(255) BINARY CHARACTER SET ascii COLLATE ascii_general_ci NOT NULL DEFAULT '' COMMENT 'Primary Key: Unique cache ID.', `data` LONGBLOB NULL DEFAULT NULL COMMENT 'A collection of data to cache.', `expire` INT NOT NULL DEFAULT 0 COMMENT 'A Unix timestamp indicating when the cache entry should expire, or -1 for never.', `created` DECIMAL(14, 3) NOT NULL DEFAULT 0 COMMENT 'A timestamp with millisecond precision indicating when the cache entry was created.', `serialized` SMALLINT NOT NULL DEFAULT 0 COMMENT 'A flag to indicate whether content is serialized (1) or not (0).', `tags` LONGTEXT NULL DEFAULT NULL COMMENT 'Space-separated list of cache tags for this entry.', `checksum` VARCHAR(255) CHARACTER SET ascii COLLATE ascii_general_ci NOT NULL COMMENT 'The tag invalidation checksum when this entry was saved.', PRIMARY KEY (`cid`), INDEX `expire` (`expire`), INDEX `created` (`created`) ) ENGINE = InnoDB DEFAULT CHARACTER SET utf8mb4 COMMENT 'Storage for the cache API.'; Array ( ) in Drupal\bootstrap\Utility\Storage->save() (line 200 of /var/www/html/etisalat_connect/themes/contrib/bootstrap/src/Utility/Storage.php).

Drupal\bootstrap\Utility\Storage->save() (Line: 1041)
_drupal_shutdown_function()