Seeing lots of these in the logs:
Expectation (writes <= 0) by MediaWiki::main not met:
query-m: UPDATE `echo_notification` SET notification_read_timestamp = 'X' AND notification_read_timestamp IS NULL
TransactionProfiler.php line 311 calls wfBacktrace()
TransactionProfiler.php line 200 calls TransactionProfiler->reportExpectationViolated()
Database.php line 1006 calls TransactionProfiler->recordQueryCompletion()
Database.php line 2001 calls DatabaseBase->query()
UserNotificationGateway.php line 56 calls DatabaseBase->update()
NotifUser.php line 338 calls EchoUserNotificationGateway->markRead()
Hooks.php line 657 calls MWEchoNotifUser->markRead()
Hooks.php line 204 calls EchoHooks::onPersonalUrls()
SkinTemplate.php line 688 calls Hooks::run()
SkinTemplate.php line 455 calls SkinTemplate->buildPersonalUrls()
SkinTemplate.php line 240 calls SkinTemplate->prepareQuickTemplate()
OutputPage.php line 2305 calls SkinTemplate->outputPage()
MediaWiki.php line 677 calls OutputPage->output()
MediaWiki.php line 474 calls MediaWiki->main()
index.php line 41 calls MediaWiki->run()
index.php line 3 calls include()