MediaWiki internal error.

Original exception: [2d2b527c53f15321e95ba9e2] /%E3%81%84%E3%81%88%E3%82%8D%EF%BD%9E%E3%81%9C%E3%81%B6%E3%82%89 RuntimeException from line 292 of /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/MediaWiki/Connection/Database.php: A connection error occurred during a query.
Query: SELECT smw_id,smw_title,smw_namespace,smw_iw,smw_subobject,smw_sortkey,smw_sort FROM `smw_object_ids` WHERE smw_hash IN ('c7c8f48df325043db26c9292fff5a8a934309658','652bf80f8fccc5040e6588a041dd302dbf5854da','ea129a82625b44673217ce6d5bac4d1d7d4e9ce9','85b1e082e5016c7c9a9bb4f70000d132177cbec7','bd74816c02fd38dfeb55f9a51acaeae7b9850910','e1db02c7fa2e2692b323103db5196b7c58cdeb37','8833215662106fec5e857dfee858a12232974adf','ff0f30f5ea808feb342cf72dd6af5e727231437b','d8ff55836e0549ed9cc3a7e62e959a470f5b7a23','cbeb976c1fe15d09c30ed8037e6fc5676a2923fb','ad30c4d83edccbbe7d2bc9ea8453e683f8e4b93f','aefd9a2cb6ee6902ccad0e8854f854bb453bcec3','e8881c297f3d37d5ff687e0dd37efd4acb3ac7cd','111ede47ae8146316260b6ab8beb868a597b76c9','d4f61b5ebd1526dc6d22ae1f2dec15d9bd585f29','d0d494479b16a923e5413b0f3b6a6dc73449576a','670186d9da6d1f44ac46cedf92668143eb9d8b1a')
Function: SMW\SQLStore\EntityStore\CacheWarmer::prefetchFromList
Error: 2006 MySQL server has gone away (localhost)

#0 /home/thwikicc/mediawiki/includes/libs/rdbms/database/Database.php(1684): Wikimedia\Rdbms\Database->getQueryException()
#1 /home/thwikicc/mediawiki/includes/libs/rdbms/database/Database.php(1659): Wikimedia\Rdbms\Database->getQueryExceptionAndLog()
#2 /home/thwikicc/mediawiki/includes/libs/rdbms/database/Database.php(1228): Wikimedia\Rdbms\Database->reportQueryError()
#3 /home/thwikicc/mediawiki/includes/libs/rdbms/database/Database.php(1908): Wikimedia\Rdbms\Database->query()
#4 /home/thwikicc/mediawiki/includes/libs/rdbms/database/DBConnRef.php(68): Wikimedia\Rdbms\Database->select()
#5 /home/thwikicc/mediawiki/includes/libs/rdbms/database/DBConnRef.php(313): Wikimedia\Rdbms\DBConnRef->__call()
#6 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/MediaWiki/Connection/Database.php(284): Wikimedia\Rdbms\DBConnRef->select()
#7 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/SQLStore/EntityStore/CacheWarmer.php(175): SMW\MediaWiki\Connection\Database->select()
#8 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/SQLStore/EntityStore/EntityIdManager.php(1128): SMW\SQLStore\EntityStore\CacheWarmer->prefetchFromList()
#9 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/MediaWiki/Hooks/ArticleViewHeader.php(83): SMW\SQLStore\EntityStore\EntityIdManager->preload()
#10 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/MediaWiki/Hooks.php(696): SMW\MediaWiki\Hooks\ArticleViewHeader->process()
#11 /home/thwikicc/mediawiki/includes/HookContainer/HookContainer.php(329): SMW\MediaWiki\Hooks->onArticleViewHeader()
#12 /home/thwikicc/mediawiki/includes/HookContainer/HookContainer.php(132): MediaWiki\HookContainer\HookContainer->callLegacyHook()
#13 /home/thwikicc/mediawiki/includes/HookContainer/HookRunner.php(886): MediaWiki\HookContainer\HookContainer->run()
#14 /home/thwikicc/mediawiki/includes/page/Article.php(719): MediaWiki\HookContainer\HookRunner->onArticleViewHeader()
#15 /home/thwikicc/mediawiki/includes/actions/ViewAction.php(80): Article->view()
#16 /home/thwikicc/mediawiki/includes/MediaWiki.php(532): ViewAction->show()
#17 /home/thwikicc/mediawiki/includes/MediaWiki.php(313): MediaWiki->performAction()
#18 /home/thwikicc/mediawiki/includes/MediaWiki.php(945): MediaWiki->performRequest()
#19 /home/thwikicc/mediawiki/includes/MediaWiki.php(548): MediaWiki->main()
#20 /home/thwikicc/mediawiki/index.php(53): MediaWiki->run()
#21 /home/thwikicc/mediawiki/index.php(46): wfIndexMain()
#22 {main}
Backtrace:
#0 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/SQLStore/EntityStore/CacheWarmer.php(175): SMW\MediaWiki\Connection\Database->select()
#1 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/SQLStore/EntityStore/EntityIdManager.php(1128): SMW\SQLStore\EntityStore\CacheWarmer->prefetchFromList()
#2 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/MediaWiki/Hooks/ArticleViewHeader.php(83): SMW\SQLStore\EntityStore\EntityIdManager->preload()
#3 /home/thwikicc/mediawiki/extensions/SemanticMediaWiki/src/MediaWiki/Hooks.php(696): SMW\MediaWiki\Hooks\ArticleViewHeader->process()
#4 /home/thwikicc/mediawiki/includes/HookContainer/HookContainer.php(329): SMW\MediaWiki\Hooks->onArticleViewHeader()
#5 /home/thwikicc/mediawiki/includes/HookContainer/HookContainer.php(132): MediaWiki\HookContainer\HookContainer->callLegacyHook()
#6 /home/thwikicc/mediawiki/includes/HookContainer/HookRunner.php(886): MediaWiki\HookContainer\HookContainer->run()
#7 /home/thwikicc/mediawiki/includes/page/Article.php(719): MediaWiki\HookContainer\HookRunner->onArticleViewHeader()
#8 /home/thwikicc/mediawiki/includes/actions/ViewAction.php(80): Article->view()
#9 /home/thwikicc/mediawiki/includes/MediaWiki.php(532): ViewAction->show()
#10 /home/thwikicc/mediawiki/includes/MediaWiki.php(313): MediaWiki->performAction()
#11 /home/thwikicc/mediawiki/includes/MediaWiki.php(945): MediaWiki->performRequest()
#12 /home/thwikicc/mediawiki/includes/MediaWiki.php(548): MediaWiki->main()
#13 /home/thwikicc/mediawiki/index.php(53): MediaWiki->run()
#14 /home/thwikicc/mediawiki/index.php(46): wfIndexMain()
#15 {main}

Exception caught inside exception handler: [2d2b527c53f15321e95ba9e2] /%E3%81%84%E3%81%88%E3%82%8D%EF%BD%9E%E3%81%9C%E3%81%B6%E3%82%89 InvalidArgumentException from line 58 of /home/thwikicc/mediawiki/includes/libs/rdbms/database/DBConnRef.php: Missing lazy connection arguments.
Backtrace:
#0 /home/thwikicc/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(1049): Wikimedia\Rdbms\DBConnRef->__construct()
#1 /home/thwikicc/mediawiki/includes/GlobalFunctions.php(2463): Wikimedia\Rdbms\LoadBalancer->getMaintenanceConnectionRef()
#2 /home/thwikicc/mediawiki/includes/block/DatabaseBlock.php(258): wfGetDB()
#3 /home/thwikicc/mediawiki/includes/block/DatabaseBlock.php(1187): MediaWiki\Block\DatabaseBlock::newLoad()
#4 /home/thwikicc/mediawiki/includes/block/BlockManager.php(146): MediaWiki\Block\DatabaseBlock::newListFromTarget()
#5 /home/thwikicc/mediawiki/includes/user/User.php(1605): MediaWiki\Block\BlockManager->getUserBlock()
#6 /home/thwikicc/mediawiki/includes/user/User.php(1991): User->getBlockedStatus()
#7 /home/thwikicc/mediawiki/extensions/FlowThread/includes/Post.php(154): User->getBlock()
#8 /home/thwikicc/mediawiki/extensions/FlowThread/includes/Hooks.php(39): FlowThread\Post::canPost()
#9 /home/thwikicc/mediawiki/includes/HookContainer/HookContainer.php(329): FlowThread\Hooks::onBeforePageDisplay()
#10 /home/thwikicc/mediawiki/includes/HookContainer/HookContainer.php(132): MediaWiki\HookContainer\HookContainer->callLegacyHook()
#11 /home/thwikicc/mediawiki/includes/HookContainer/HookRunner.php(991): MediaWiki\HookContainer\HookContainer->run()
#12 /home/thwikicc/mediawiki/includes/OutputPage.php(2617): MediaWiki\HookContainer\HookRunner->onBeforePageDisplay()
#13 /home/thwikicc/mediawiki/includes/exception/MWExceptionRenderer.php(153): OutputPage->output()
#14 /home/thwikicc/mediawiki/includes/exception/MWExceptionRenderer.php(65): MWExceptionRenderer::reportHTML()
#15 /home/thwikicc/mediawiki/includes/exception/MWExceptionHandler.php(106): MWExceptionRenderer::output()
#16 /home/thwikicc/mediawiki/includes/exception/MWExceptionHandler.php(185): MWExceptionHandler::report()
#17 /home/thwikicc/mediawiki/includes/MediaWiki.php(581): MWExceptionHandler::handleException()
#18 /home/thwikicc/mediawiki/index.php(53): MediaWiki->run()
#19 /home/thwikicc/mediawiki/index.php(46): wfIndexMain()
#20 {main}