[Bitrix\Main\DB\SqlQueryException] 
Mysql query error: (2006) MySQL server has gone away (400)
SELECT 'x' FROM b_module_to_module WHERE FROM_MODULE_ID='main'	AND MESSAGE_ID='OnAfterUserLogout' 	AND TO_MODULE_ID='' 	AND TO_CLASS='' 	AND TO_METHOD='OnAfterUserLogoutHandler' AND (TO_PATH='' OR TO_PATH IS NULL) AND (TO_METHOD_ARG='' OR TO_METHOD_ARG IS NULL)
/home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:137
#0: Bitrix\Main\DB\MysqliConnection->queryInternal(string, array, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:329
#1: Bitrix\Main\DB\Connection->query(string)
	/home/bitrix/www/bitrix/modules/main/lib/eventmanager.php:185
#2: Bitrix\Main\EventManager->registerEventHandlerInternal(string, string, string, string, string, integer, string, string, integer)
	/home/bitrix/www/bitrix/modules/main/lib/eventmanager.php:156
#3: Bitrix\Main\EventManager->registerEventHandlerCompatible(string, string, string, string, string, integer, string, array)
	/home/bitrix/www/bitrix/modules/main/classes/general/module.php:507
#4: RegisterModuleDependences(string, string, string, string, string)
	/home/bitrix/www/bitrix/php_interface/init.php:22
#5: include_once(string)
	/home/bitrix/www/bitrix/modules/main/include.php:232
#6: require_once(string)
	/home/bitrix/www/bitrix/modules/main/include/prolog_before.php:14
#7: require_once(string)
	/home/bitrix/www/bitrix/modules/main/include/prolog.php:10
#8: require_once(string)
	/home/bitrix/www/bitrix/header.php:1
#9: require(string)
	/home/bitrix/www/board/my/index.php:2