This affects page parses and some special pages. Requiring the master DB just for parsing is bad for HA and blocks active/active multi-DC use.
```
[GET] Expectation (masterConns <= 0) by MediaWiki::main not met:
[connect to 10.64.32.28 (wikidatawiki)]
TransactionProfiler.php line 307 calls wfBacktrace()
TransactionProfiler.php line 146 calls TransactionProfiler->reportExpectationViolated()
LoadBalancer.php line 545 calls TransactionProfiler->recordConnection()
DBAccessBase.php line 61 calls LoadBalancer->getConnection()
WikiPageEntityMetaDataLookup.php line 161 calls DBAccessBase->getConnection()
WikiPageEntityMetaDataLookup.php line 70 calls Wikibase\Lib\Store\Sql\WikiPageEntityMetaDataLookup->selectRevisionInformationMultiple()
PrefetchingWikiPageEntityMetaDataAccessor.php line 148 calls Wikibase\Lib\Store\Sql\WikiPageEntityMetaDataLookup->loadRevisionInformation()
WikiPageEntityRevisionLookup.php line 78 calls Wikibase\Lib\Store\Sql\PrefetchingWikiPageEntityMetaDataAccessor->loadRevisionInformation()
SpecialWikibaseRepoPage.php line 163 calls Wikibase\Lib\Store\WikiPageEntityRevisionLookup->getEntityRevision()
SpecialModifyEntity.php line 127 calls Wikibase\Repo\Specials\SpecialWikibaseRepoPage->loadEntity()
SpecialSetSiteLink.php line 103 calls Wikibase\Repo\Specials\SpecialModifyEntity->prepareArguments()
SpecialModifyEntity.php line 76 calls Wikibase\Repo\Specials\SpecialSetSiteLink->prepareArguments()
SpecialPage.php line 384 calls Wikibase\Repo\Specials\SpecialModifyEntity->execute()
SpecialPageFactory.php line 553 calls SpecialPage->run()
MediaWiki.php line 249 calls SpecialPageFactory::executePath()
MediaWiki.php line 683 calls MediaWiki->performRequest()
MediaWiki.php line 474 calls MediaWiki->main()
index.php line 41 calls MediaWiki->run()
index.php line 3 calls include()
```
```
Expectation (masterConns <= 0) by MediaWiki::main not met:
[connect to 10.64.16.144 (wikidatawiki)]
TransactionProfiler.php line 311 calls wfBacktrace()
TransactionProfiler.php line 146 calls TransactionProfiler->reportExpectationViolated()
LoadBalancer.php line 576 calls TransactionProfiler->recordConnection()
DBAccessBase.php line 61 calls LoadBalancer->getConnection()
WikiPageEntityMetaDataLookup.php line 160 calls DBAccessBase->getConnection()
WikiPageEntityMetaDataLookup.php line 69 calls Wikibase\Lib\Store\Sql\WikiPageEntityMetaDataLookup->selectRevisionInformationMultiple()
PrefetchingWikiPageEntityMetaDataAccessor.php line 193 calls Wikibase\Lib\Store\Sql\WikiPageEntityMetaDataLookup->loadRevisionInformation()
PrefetchingWikiPageEntityMetaDataAccessor.php line 162 calls Wikibase\Lib\Store\Sql\PrefetchingWikiPageEntityMetaDataAccessor->doFetch()
WikiPageEntityRevisionLookup.php line 81 calls Wikibase\Lib\Store\Sql\PrefetchingWikiPageEntityMetaDataAccessor->loadRevisionInformation()
CachingEntityRevisionLookup.php line 149 calls Wikibase\Lib\Store\WikiPageEntityRevisionLookup->getEntityRevision()
CachingEntityRevisionLookup.php line 132 calls Wikibase\Lib\Store\CachingEntityRevisionLookup->fetchEntityRevision()
CachingEntityRevisionLookup.php line 149 calls Wikibase\Lib\Store\CachingEntityRevisionLookup->getEntityRevision()
CachingEntityRevisionLookup.php line 132 calls Wikibase\Lib\Store\CachingEntityRevisionLookup->fetchEntityRevision()
RevisionBasedEntityLookup.php line 44 calls Wikibase\Lib\Store\CachingEntityRevisionLookup->getEntityRevision()
RedirectResolvingEntityLookup.php line 51 calls Wikibase\Lib\Store\RevisionBasedEntityLookup->getEntity()
EntityRetrievingTermLookup.php line 131 calls Wikibase\DataModel\Services\Lookup\RedirectResolvingEntityLookup->getEntity()
EntityRetrievingTermLookup.php line 116 calls Wikibase\DataModel\Services\Lookup\EntityRetrievingTermLookup->fetchFingerprint()
EntityRetrievingTermLookup.php line 64 calls Wikibase\DataModel\Services\Lookup\EntityRetrievingTermLookup->getFingerprint()
UsageTrackingTermLookup.php line 64 calls Wikibase\DataModel\Services\Lookup\EntityRetrievingTermLookup->getLabels()
LanguageFallbackLabelDescriptionLookup.php line 55 calls Wikibase\Client\Usage\UsageTrackingTermLookup->getLabels()
WikibaseLuaBindings.php line 138 calls Wikibase\Lib\Store\LanguageFallbackLabelDescriptionLookup->getLabel()
Scribunto_LuaWikibaseLibrary.php line 364 calls Wikibase\Client\DataAccess\Scribunto\WikibaseLuaBindings->getLabel()
Engine.php line 407 calls Wikibase\Client\DataAccess\Scribunto\Scribunto_LuaWikibaseLibrary->getLabel()
- line - calls Scribunto_LuaSandboxCallback->__call()
Engine.php line 319 calls LuaSandboxFunction->call()
LuaCommon.php line 243 calls Scribunto_LuaSandboxInterpreter->callFunction()
LuaCommon.php line 887 calls Scribunto_LuaEngine->executeModule()
Hooks.php line 121 calls Scribunto_LuaModule->invoke()
Parser.php line 3347 calls ScribuntoHooks::invokeHook()
Parser.php line 3082 calls Parser->callParserFunction()
Preprocessor_Hash.php line 1075 calls Parser->braceSubstitution()
Parser.php line 3224 calls PPFrame_Hash->expand()
Preprocessor_Hash.php line 1075 calls Parser->braceSubstitution()
Parser.php line 2896 calls PPFrame_Hash->expand()
Parser.php line 1259 calls Parser->replaceVariables()
Parser.php line 439 calls Parser->internalParse()
WikitextContent.php line 331 calls Parser->parse()
AbstractContent.php line 497 calls WikitextContent->fillParserOutput()
PoolWorkArticleView.php line 140 calls AbstractContent->getParserOutput()
PoolCounterWork.php line 123 calls PoolWorkArticleView->doWork()
Article.php line 666 calls PoolCounterWork->execute()
ViewAction.php line 44 calls Article->view()
MediaWiki.php line 504 calls ViewAction->show()
MediaWiki.php line 288 calls MediaWiki->performAction()
MediaWiki.php line 746 calls MediaWiki->performRequest()
MediaWiki.php line 520 calls MediaWiki->main()
index.php line 43 calls MediaWiki->run()
index.php line 3 calls include()
```