#12188 Wiki can’t connect to database
Closed: Fixed 9 months ago by nphilipp. Opened 9 months ago by nphilipp.

Accessing https://fedoraproject.org/wiki/Architectures, I often get this error (but not always):

MediaWiki internal error.

Original exception: [ZuvbCSer93RCVHVMl8GfVgAAAZY] /wiki/Architectures Wikimedia\Rdbms\DBConnectionError: Cannot access the database: Too many connections (db03)
Backtrace:
from /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(1149)
#0 /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(805): Wikimedia\Rdbms\LoadBalancer->reportConnectionError()
#1 /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(793): Wikimedia\Rdbms\LoadBalancer->getServerConnection()
#2 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(99): Wikimedia\Rdbms\LoadBalancer->getConnectionInternal()
#3 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(117): Wikimedia\Rdbms\DBConnRef->ensureConnection()
#4 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(369): Wikimedia\Rdbms\DBConnRef->__call()
#5 /usr/share/mediawiki/includes/page/WikiPage.php(358): Wikimedia\Rdbms\DBConnRef->selectRow()
#6 /usr/share/mediawiki/includes/page/WikiPage.php(386): WikiPage->pageData()
#7 /usr/share/mediawiki/includes/page/WikiPage.php(426): WikiPage->pageDataFromTitle()
#8 /usr/share/mediawiki/includes/page/WikiPage.php(542): WikiPage->loadPageData()
#9 /usr/share/mediawiki/includes/page/WikiPage.php(614): WikiPage->exists()
#10 /usr/share/mediawiki/includes/page/WikiPage.php(251): WikiPage->getContentModel()
#11 /usr/share/mediawiki/includes/MediaWiki.php(480): WikiPage->getContentHandler()
#12 /usr/share/mediawiki/includes/MediaWiki.php(361): MediaWiki->initializeArticle()
#13 /usr/share/mediawiki/includes/MediaWiki.php(960): MediaWiki->performRequest()
#14 /usr/share/mediawiki/includes/MediaWiki.php(613): MediaWiki->main()
#15 /usr/share/mediawiki/index.php(50): MediaWiki->run()
#16 /usr/share/mediawiki/index.php(46): wfIndexMain()
#17 {main}

Exception caught inside exception handler: [ZuvbCSer93RCVHVMl8GfVgAAAZY] /wiki/Architectures Wikimedia\Rdbms\DBConnectionError: Cannot access the database: Too many connections (db03)
Backtrace:
from /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(1149)
#0 /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(805): Wikimedia\Rdbms\LoadBalancer->reportConnectionError()
#1 /usr/share/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(793): Wikimedia\Rdbms\LoadBalancer->getServerConnection()
#2 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(99): Wikimedia\Rdbms\LoadBalancer->getConnectionInternal()
#3 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(117): Wikimedia\Rdbms\DBConnRef->ensureConnection()
#4 /usr/share/mediawiki/includes/libs/rdbms/database/DBConnRef.php(338): Wikimedia\Rdbms\DBConnRef->__call()
#5 /usr/share/mediawiki/includes/libs/rdbms/querybuilder/SelectQueryBuilder.php(725): Wikimedia\Rdbms\DBConnRef->selectField()
#6 /usr/share/mediawiki/includes/language/LCStoreDB.php(65): Wikimedia\Rdbms\SelectQueryBuilder->fetchField()
#7 /usr/share/mediawiki/includes/language/LocalisationCache.php(559): LCStoreDB->get()
#8 /usr/share/mediawiki/includes/language/LocalisationCache.php(606): LocalisationCache->isExpired()
#9 /usr/share/mediawiki/includes/language/LocalisationCache.php(516): LocalisationCache->initLanguage()
#10 /usr/share/mediawiki/includes/language/LocalisationCache.php(396): LocalisationCache->loadSubitem()
#11 /usr/share/mediawiki/includes/language/MessageCache.php(745): LocalisationCache->getSubitem()
#12 /usr/share/mediawiki/includes/language/MessageCache.php(1323): MessageCache->isMainCacheable()
#13 /usr/share/mediawiki/includes/language/MessageCache.php(1205): MessageCache->getMsgFromNamespace()
#14 /usr/share/mediawiki/includes/language/MessageCache.php(1177): MessageCache->getMessageForLang()
#15 /usr/share/mediawiki/includes/language/MessageCache.php(1072): MessageCache->getMessageFromFallbackChain()
#16 /usr/share/mediawiki/includes/language/Message.php(1485): MessageCache->get()
#17 /usr/share/mediawiki/includes/language/Message.php(972): Message->fetchMessage()
#18 /usr/share/mediawiki/includes/language/Message.php(1059): Message->format()
#19 /usr/share/mediawiki/includes/exception/MWExceptionRenderer.php(254): Message->text()
#20 /usr/share/mediawiki/includes/exception/MWExceptionRenderer.php(398): MWExceptionRenderer::msg()
#21 /usr/share/mediawiki/includes/exception/MWExceptionRenderer.php(103): MWExceptionRenderer::reportOutageHTML()
#22 /usr/share/mediawiki/includes/exception/MWExceptionHandler.php(134): MWExceptionRenderer::output()
#23 /usr/share/mediawiki/includes/exception/MWExceptionHandler.php(251): MWExceptionHandler::report()
#24 /usr/share/mediawiki/includes/MediaWiki.php(632): MWExceptionHandler::handleException()
#25 /usr/share/mediawiki/index.php(50): MediaWiki->run()
#26 /usr/share/mediawiki/index.php(46): wfIndexMain()
#27 {main}

When I reload the page, it’s about a coin toss (50%/50%) if the page loads successfully or runs into the error. I get either via the same proxies.

This should display the page instead.

When do you need this to be done by? (YYYY/MM/DD)

Soon


Metadata Update from @zlopez:
- Issue priority set to: Waiting on Assignee (was: Needs Review)
- Issue tagged with: Needs investigation

9 months ago

This is happening only for some proxies, if you hit the working ones it will redirect you without issue.

It seems that this was resolved by itself. I don't see any more alerts in nagios. Could you confirm that it's working for you?

So, in the past this has been when database backups are running, the wiki is slow/unresponsive. ;(

It may be that there's some kind of leak in mariadb and restarting it will help... I did so, so I guess we can see if it happens the next database backup window.

I don’t get these errors anymore.

Metadata Update from @nphilipp:
- Issue close_status updated to: Fixed
- Issue status updated to: Closed (was: Open)

9 months ago

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