[Bitrix\Main\DB\SqlQueryException] 
Mysql query error: (2006) MySQL server has gone away (400)
SHOW TABLES LIKE 'b_iblock_2_index_val'
/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)
	/home/bitrix/www/bitrix/modules/main/lib/db/mysqlcommonconnection.php:52
#2: Bitrix\Main\DB\MysqlCommonConnection->isTableExists(string)
	/home/bitrix/www/bitrix/modules/iblock/lib/propertyindex/dictionary.php:54
#3: Bitrix\Iblock\PropertyIndex\Dictionary->isExists()
	/home/bitrix/www/bitrix/modules/iblock/lib/propertyindex/facet.php:57
#4: Bitrix\Iblock\PropertyIndex\Facet->__construct(integer)
	/home/bitrix/www/bitrix/modules/iblock/lib/propertyindex/querybuilder.php:28
#5: Bitrix\Iblock\PropertyIndex\QueryBuilder->__construct(integer)
	/home/bitrix/www/bitrix/modules/iblock/classes/general/iblockelement.php:657
#6: CAllIBlockElement->MkFilter(array, array, array)
	/home/bitrix/www/bitrix/modules/iblock/classes/general/iblockelement.php:3088
#7: CAllIBlockElement->PrepareGetList(array, array, array, string, array, array, NULL, NULL, array, boolean, string, array, array, array)
	/home/bitrix/www/bitrix/modules/iblock/classes/mysql/iblockelement.php:343
#8: CIBlockElement->prepareSql(array, array, boolean, array)
	/home/bitrix/www/bitrix/modules/iblock/classes/mysql/iblockelement.php:662
#9: CIBlockElement::GetList(array, array, boolean, boolean, array)
	/home/bitrix/www/bitrix/modules/iblock/classes/general/comp_findtools.php:25
#10: CIBlockFindTools::GetElementID(integer, string, integer, string, array)
	/home/bitrix/www/bitrix/modules/iblock/lib/component/element.php:322
#11: Bitrix\Iblock\Component\Element->checkElementId()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/element.php:284
#12: Bitrix\Iblock\Component\Element->processResultData()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:4453
#13: Bitrix\Iblock\Component\Base->loadData()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:4442
#14: Bitrix\Iblock\Component\Base->initialLoadAction()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/element.php:271
#15: Bitrix\Iblock\Component\Element->initialLoadAction()
	
#16: call_user_func(array)
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:4627
#17: Bitrix\Iblock\Component\Base->doAction()
	/home/bitrix/www/bitrix/modules/iblock/lib/component/base.php:4645
#18: Bitrix\Iblock\Component\Base->executeComponent()
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:649
#19: CBitrixComponent->includeComponent(string, array, object)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:1039
#20: CAllMain->IncludeComponent(string, string, array, object)
	/home/bitrix/www/bitrix/templates/opthz_copy/components/bitrix/catalog/opthz/element.php:227
#21: include(string)
	/home/bitrix/www/bitrix/modules/main/classes/general/component_template.php:725
#22: CBitrixComponentTemplate->__IncludePHPTemplate(array, array, string)
	/home/bitrix/www/bitrix/modules/main/classes/general/component_template.php:820
#23: CBitrixComponentTemplate->IncludeTemplate(array)
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:746
#24: CBitrixComponent->showComponentTemplate()
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:694
#25: CBitrixComponent->includeComponentTemplate(string)
	/home/bitrix/www/bitrix/components/bitrix/catalog/component.php:171
#26: include(string)
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:605
#27: CBitrixComponent->__includeComponent()
	/home/bitrix/www/bitrix/modules/main/classes/general/component.php:664
#28: CBitrixComponent->includeComponent(string, array, NULL)
	/home/bitrix/www/bitrix/modules/main/classes/general/main.php:1039
#29: CAllMain->IncludeComponent(string, string, array)
	/home/bitrix/www/catalog/index.php:10
#30: include_once(string)
	/home/bitrix/www/bitrix/modules/main/include/urlrewrite.php:159
#31: include_once(string)
	/home/bitrix/www/bitrix/urlrewrite.php:2

Fatal error: Uncaught Bitrix\Main\DB\SqlQueryException: Mysql query error: (2006) MySQL server has gone away in /home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php:137 Stack trace: #0 /home/bitrix/www/bitrix/modules/main/lib/db/connection.php(330): Bitrix\Main\DB\MysqliConnection->queryInternal('SELECT \n\t`main_...', Array, NULL) #1 /home/bitrix/www/bitrix/modules/main/lib/orm/query/query.php(3304): Bitrix\Main\DB\Connection->query('SELECT \n\t`main_...') #2 /home/bitrix/www/bitrix/modules/main/lib/orm/query/query.php(816): Bitrix\Main\ORM\Query\Query->query('SELECT \n\t`main_...') #3 /home/bitrix/www/bitrix/modules/main/lib/orm/data/datamanager.php(500): Bitrix\Main\ORM\Query\Query->exec() #4 /home/bitrix/www/bitrix/modules/main/lib/analytics/sitespeed.php(95): Bitrix\Main\ORM\Data\DataManager::getList(Array) #5 /home/bitrix/www/bitrix/modules/main/lib/analytics/counter.php(92): Bitrix\Main\Analytics\SiteSpeed::isIntranetSite('s1') #6 /home/bitrix/www/bitrix/modules/main/classes/general/module.php(490): Bit in /home/bitrix/www/bitrix/modules/main/lib/db/mysqliconnection.php on line 137