Seeing a lot of "mysql server has gone away" since 11

ℹ️ Support
1

Here’s an example:

Error	no app in context	Doctrine\DBAL\Exception\DriverException: An exception occurred while executing 'SELECT `fileid`, `storage`, `path`, `parent`, `name`, `mimetype`, `mimepart`, `size`, `mtime`, `storage_mtime`, `encrypted`, `etag`, `permissions`, `checksum` FROM `oc_filecache` WHERE `storage` = ? AND `path_hash` = ?' with params [1, "e060ffed0cd91047d2f249d54f724341"]: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away
/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/DBALException.php - line 128: Doctrine\DBAL\Driver\AbstractMySQLDriver->convertException('An exception oc...', Object(Doctrine\DBAL\Driver\PDOException))
/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php - line 836: Doctrine\DBAL\DBALException driverExceptionDuringQuery(Object(Doctrine\DBAL\Driver\PDOMySql\Driver), Object(Doctrine\DBAL\Driver\PDOException), 'SELECT `fileid`...', Array)
/var/www/html/lib/private/DB/Connection.php - line 194: Doctrine\DBAL\Connection->executeQuery('SELECT `fileid`...', Array, Array, NULL)
/var/www/html/lib/private/Files/Cache/Cache.php - line 129: OC\DB\Connection->executeQuery('SELECT `fileid`...', Array)
/var/www/html/lib/private/Files/Cache/HomeCache.php - line 76: OC\Files\Cache\Cache->get('files/Software/...')
/var/www/html/lib/private/Files/Storage/Wrapper/Encryption.php - line 141: OC\Files\Cache\HomeCache->get('files/Software/...')
/var/www/html/lib/private/Files/Storage/Wrapper/Wrapper.php - line 149: OC\Files\Storage\Wrapper\Encryption->filesize('files/Software/...')
/var/www/html/lib/private/Files/Storage/Wrapper/Wrapper.php - line 149: OC\Files\Storage\Wrapper\Wrapper->filesize('files/Software/...')
/var/www/html/lib/private/Files/Storage/Wrapper/Wrapper.php - line 149: OC\Files\Storage\Wrapper\Wrapper->filesize('files/Software/...')
/var/www/html/lib/private/Files/View.php - line 1124: OC\Files\Storage\Wrapper\Wrapper->filesize('files/Software/...')
/var/www/html/lib/private/Files/View.php - line 418: OC\Files\View->basicOperation('filesize', '/Software/Nextc...')
/var/www/html/lib/private/Files/View.php - line 437: OC\Files\View->filesize('/Software/Nextc...')
/var/www/html/lib/private/legacy/files.php - line 305: OC\Files\View->readfile('/Software/Nextc...')
/var/www/html/lib/private/legacy/files.php - line 120: OC_Files getSingleFile(Object(OC\Files\View), '/Software/Nextc...', 'gnome_disk_imag...', Array)
/var/www/html/apps/files_sharing/lib/Controller/ShareController.php - line 529: OC_Files get('/Software/Nextc...', 'gnome_disk_imag...', Array)
[internal function] OCA\Files_Sharing\Controller\ShareController->downloadShare('WjFAGflV2tDfWaI', 'gnome_disk_imag...', '/', '')
/var/www/html/lib/private/AppFramework/Http/Dispatcher.php - line 160: call_user_func_array(Array, Array)
/var/www/html/lib/private/AppFramework/Http/Dispatcher.php - line 90: OC\AppFramework\Http\Dispatcher->executeController(Object(OCA\Files_Sharing\Controller\ShareController), 'downloadShare')
/var/www/html/lib/private/AppFramework/App.php - line 114: OC\AppFramework\Http\Dispatcher->dispatch(Object(OCA\Files_Sharing\Controller\ShareController), 'downloadShare')
/var/www/html/lib/public/AppFramework/App.php - line 136: OC\AppFramework\App main('ShareController', 'downloadShare', Object(OC\AppFramework\DependencyInjection\DIContainer))
/var/www/html/core/routes.php - line 100: OCP\AppFramework\App->dispatch('ShareController', 'downloadShare')
[internal function] OC\Route\Router->{closure}(Array)
/var/www/html/lib/private/Route/Router.php - line 299: call_user_func(Object(Closure), Array)
/var/www/html/lib/base.php - line 1010: OC\Route\Router->match('/s/WjFAGflV2tDf...')
/var/www/html/index.php - line 40: OC handleRequest()
{main}

I’m not seeing any detrimental behaviour while I’m uploading/navigating around the server, and the database is external - shared amongst several applications that don’t report any database issues.

2

Did you check all the timeout settings for your database (also in php for mysql-connections)?

3

Yes, I’d tweaked those also for the reasons the db is not on localhost. I know there’s been a substantial change around the db connections in 11 so I’m now wondering if there are recommended settings I should follow to go with it.

Regardless, the db server is a container much like the nc server, all on the same host connecting via private vlan so there should really be almost 0 latency.