[Bitrix\Main\DB\SqlQueryException] 
Mysql query error: (2006) MySQL server has gone away (400)
SELECT GET_LOCK("9d64f9ec9b005a43a16db6ad94e2f966", 60)
LIMIT 0, 1

/app/bitrix/modules/main/lib/db/mysqliconnection.php:137
#0: Bitrix\Main\DB\MysqliConnection->queryInternal(string, NULL, NULL)
	/app/bitrix/modules/main/lib/db/connection.php:330
#1: Bitrix\Main\DB\Connection->query(string, NULL, integer, integer)
	/app/bitrix/modules/main/lib/db/connection.php:358
#2: Bitrix\Main\DB\Connection->queryScalar(string)
	/app/bitrix/modules/main/lib/session/handlers/table/usersessiontable.php:100
#3: Bitrix\Main\Session\Handlers\Table\UserSessionTable::lock(string)
	/app/bitrix/modules/main/lib/session/handlers/databasesessionhandler.php:50
#4: Bitrix\Main\Session\Handlers\DatabaseSessionHandler->lock(string)
	/app/bitrix/modules/main/lib/session/handlers/abstractsessionhandler.php:50
#5: Bitrix\Main\Session\Handlers\AbstractSessionHandler->read(string)
	/app/bitrix/modules/main/lib/session/handlers/abstractsessionhandler.php:162
#6: Bitrix\Main\Session\Handlers\AbstractSessionHandler->validateId(string)
	
#7: session_start()
	/app/bitrix/modules/main/lib/session/session.php:125
#8: Bitrix\Main\Session\Session->start()
	/app/bitrix/modules/main/lib/session/kernelsessionproxy.php:42
#9: Bitrix\Main\Session\KernelSessionProxy->start()
	/app/bitrix/modules/main/include.php:189
#10: require_once(string)
	/app/bitrix/modules/main/include/prolog_before.php:14
#11: require_once(string)
	/app/bitrix/modules/main/include/prolog.php:10
#12: require_once(string)
	/app/bitrix/header.php:1
#13: require(string)
	/app/catalog/index.php:4
#14: include_once(string)
	/app/local/include/urlrewrite.php:177
#15: include_once(string)
	/app/local/include/custom_urlrewrite.php:3