[Bitrix\Main\DB\SqlQueryException] 
Mysql query error: (2006) MySQL server has gone away (400)
DO RELEASE_LOCK('b8bb4c61a7dd5b90249a84ebd3bdd10e')
/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:330
#1: Bitrix\Main\DB\Connection->query(string, NULL)
	/home/bitrix/www/bitrix/modules/main/lib/db/connection.php:379
#2: Bitrix\Main\DB\Connection->queryExecute(string)
	/home/bitrix/www/bitrix/modules/main/lib/composite/internals/locker.php:46
#3: Bitrix\Main\Composite\Internals\Locker::unlock(string)
	/home/bitrix/www/bitrix/modules/main/lib/composite/engine.php:494
#4: Bitrix\Main\Composite\Engine::processPageContent(string)
	/home/bitrix/www/bitrix/modules/main/lib/composite/engine.php:420
#5: Bitrix\Main\Composite\Engine::endBuffering(string, string)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:3194
#6: CAllMain->EndBufferContent(string)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:3138
#7: CAllMain->EndBufferContentMan()
	/home/bitrix/www/bitrix/modules/main/include/epilog_after.php:36
#8: require(string)
	/home/bitrix/www/bitrix/modules/main/include/epilog.php:3
#9: require_once(string)
	/home/bitrix/www/bitrix/footer.php:4
#10: require(string)
	/home/bitrix/www/product/index.php:385
#11: include_once(string)
	/home/bitrix/www/bitrix/modules/main/include/urlrewrite.php:159
#12: include_once(string)
	/home/bitrix/www/bitrix/urlrewrite.php:2