MediaWiki internal error.

Original exception: [55d2ac51880530bb63f5e5bc] /raksti/Likums_%22Par_presi%22 Wikimedia\Rdbms\DBQueryError from line 1496 of /var/lib/mediawiki/includes/libs/rdbms/database/Database.php: A connection error occurred.
Query: SELECT page_id,page_len,page_is_redirect,page_latest,page_content_model FROM `wik2page` WHERE page_namespace = '8' AND page_title = 'Tooltip-n-Prese.2C-radio.2C-TV/en' LIMIT 1
Function: LinkCache::fetchPageRow
Error: 2006 MySQL server has gone away (localhost)

Backtrace:
#0 /var/lib/mediawiki/includes/libs/rdbms/database/Database.php(1466): Wikimedia\Rdbms\Database->makeQueryException(string, integer, string, string)
#1 /var/lib/mediawiki/includes/libs/rdbms/database/Database.php(1226): Wikimedia\Rdbms\Database->reportQueryError(string, integer, string, string, boolean)
#2 /var/lib/mediawiki/includes/libs/rdbms/database/Database.php(1693): Wikimedia\Rdbms\Database->query(string, string)
#3 /var/lib/mediawiki/includes/libs/rdbms/database/Database.php(1784): Wikimedia\Rdbms\Database->select(string, array, array, string, array, array)
#4 /var/lib/mediawiki/includes/cache/LinkCache.php(312): Wikimedia\Rdbms\Database->selectRow(string, array, array, string)
#5 /var/lib/mediawiki/includes/cache/LinkCache.php(270): LinkCache->fetchPageRow(Wikimedia\Rdbms\DatabaseMysqli, Title)
#6 /var/lib/mediawiki/includes/Title.php(3575): LinkCache->addLinkObj(Title)
#7 /var/lib/mediawiki/includes/Revision/RevisionStore.php(2719): Title->getArticleID()
#8 /var/lib/mediawiki/includes/Revision.php(1308): MediaWiki\Revision\RevisionStore->getKnownCurrentRevision(Title, integer)
#9 /var/lib/mediawiki/includes/cache/MessageCache.php(1117): Revision::newKnownCurrent(Wikimedia\Rdbms\DatabaseMysqli, Title)
#10 /var/lib/mediawiki/includes/libs/objectcache/WANObjectCache.php(1277): MessageCache->{closure}(boolean, integer, array, NULL)
#11 /var/lib/mediawiki/includes/libs/objectcache/WANObjectCache.php(1150): WANObjectCache->doGetWithSetCallback(string, integer, Closure, array)
#12 /var/lib/mediawiki/includes/cache/MessageCache.php(1143): WANObjectCache->getWithSetCallback(string, integer, Closure)
#13 /var/lib/mediawiki/includes/libs/objectcache/BagOStuff.php(168): MessageCache->{closure}()
#14 /var/lib/mediawiki/includes/cache/MessageCache.php(1145): BagOStuff->getWithSetCallback(string, integer, Closure)
#15 /var/lib/mediawiki/includes/cache/MessageCache.php(1061): MessageCache->loadCachedMessagePageEntry(string, string, string)
#16 /var/lib/mediawiki/includes/cache/MessageCache.php(985): MessageCache->getMsgFromNamespace(string, string)
#17 /var/lib/mediawiki/includes/cache/MessageCache.php(928): MessageCache->getMessageForLang(Language, string, boolean, array)
#18 /var/lib/mediawiki/includes/cache/MessageCache.php(870): MessageCache->getMessageFromFallbackChain(Language, string, boolean)
#19 /var/lib/mediawiki/includes/Message.php(1299): MessageCache->get(string, boolean, Language)
#20 /var/lib/mediawiki/includes/Message.php(991): Message->fetchMessage()
#21 /var/lib/mediawiki/includes/Linker.php(1969): Message->exists()
#22 /var/lib/mediawiki/includes/Linker.php(2142): Linker::titleAttrib(string, array, array)
#23 /var/lib/mediawiki/includes/skins/BaseTemplate.php(428): Linker::tooltipAndAccesskeyAttribs(string, array, array)
#24 /var/lib/mediawiki/includes/skins/BaseTemplate.php(507): BaseTemplate->makeLink(integer, array, array)
#25 /var/lib/mediawiki/skins/Timeless/includes/TimelessTemplate.php(274): BaseTemplate->makeListItem(integer, array, array)
#26 /var/lib/mediawiki/skins/Timeless/includes/TimelessTemplate.php(450): TimelessTemplate->getPortlet(string, array)
#27 /var/lib/mediawiki/skins/Timeless/includes/TimelessTemplate.php(162): TimelessTemplate->getMainNavigation()
#28 /var/lib/mediawiki/includes/skins/SkinTemplate.php(227): TimelessTemplate->execute()
#29 /var/lib/mediawiki/includes/OutputPage.php(2706): SkinTemplate->outputPage()
#30 /var/lib/mediawiki/includes/MediaWiki.php(867): OutputPage->output(boolean)
#31 /var/lib/mediawiki/includes/MediaWiki.php(879): MediaWiki->{closure}()
#32 /var/lib/mediawiki/includes/MediaWiki.php(517): MediaWiki->main()
#33 /var/lib/mediawiki/index.php(46): MediaWiki->run()
#34 {main}

Exception caught inside exception handler: [55d2ac51880530bb63f5e5bc] /raksti/Likums_%22Par_presi%22 Wikimedia\Rdbms\DBConnectionError from line 1195 of /var/lib/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php: Cannot access the database: Unknown error (localhost)
Backtrace:
#0 /var/lib/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(769): Wikimedia\Rdbms\LoadBalancer->reportConnectionError()
#1 /var/lib/mediawiki/includes/GlobalFunctions.php(2694): Wikimedia\Rdbms\LoadBalancer->getConnection(integer, array, boolean)
#2 /var/lib/mediawiki/includes/cache/localisation/LCStoreDB.php(54): wfGetDB(integer)
#3 /var/lib/mediawiki/includes/cache/localisation/LocalisationCache.php(391): LCStoreDB->get(string, string)
#4 /var/lib/mediawiki/includes/cache/localisation/LocalisationCache.php(294): LocalisationCache->loadSubitem(string, string, string)
#5 /var/lib/mediawiki/languages/Language.php(2643): LocalisationCache->getSubitem(string, string, string)
#6 /var/lib/mediawiki/includes/cache/MessageCache.php(970): Language->getMessage(string)
#7 /var/lib/mediawiki/includes/cache/MessageCache.php(928): MessageCache->getMessageForLang(Language, string, boolean, array)
#8 /var/lib/mediawiki/includes/cache/MessageCache.php(870): MessageCache->getMessageFromFallbackChain(Language, string, boolean)
#9 /var/lib/mediawiki/includes/Message.php(1299): MessageCache->get(string, boolean, Language)
#10 /var/lib/mediawiki/includes/Message.php(851): Message->fetchMessage()
#11 /var/lib/mediawiki/includes/Message.php(943): Message->toString(string)
#12 /var/lib/mediawiki/includes/exception/MWExceptionRenderer.php(132): Message->text()
#13 /var/lib/mediawiki/includes/exception/MWExceptionRenderer.php(53): MWExceptionRenderer::reportHTML(Wikimedia\Rdbms\DBQueryError)
#14 /var/lib/mediawiki/includes/exception/MWExceptionHandler.php(98): MWExceptionRenderer::output(Wikimedia\Rdbms\DBQueryError, integer)
#15 /var/lib/mediawiki/includes/exception/MWExceptionHandler.php(172): MWExceptionHandler::report(Wikimedia\Rdbms\DBQueryError)
#16 /var/lib/mediawiki/includes/MediaWiki.php(544): MWExceptionHandler::handleException(Wikimedia\Rdbms\DBQueryError)
#17 /var/lib/mediawiki/index.php(46): MediaWiki->run()
#18 {main}

Warning: Error while sending QUERY packet. PID=2657845 in /var/lib/mediawiki/includes/libs/rdbms/database/DatabaseMysqli.php on line 46