We're troubleshooting some slow site transactions on our site. We've see requests to attachments from index.php that are loading slowly. NewRelic shows a big lag in response from XenForo_FileOutput, where it took 12,600 ms for this function to respond. Slowest components Count Duration % XenForo_FileOutput:utput 1 12,600 ms 100% Memcache get 27 16 ms 0% /index.php 1 5 ms 0% XenForo_Model_DataRegistry::getMulti 1 4 ms 0% XenForo_FrontController::run 1 3 ms 0% XenForo_Visitor::setup 1 3 ms 0% Remainder 1 21 ms 0% Total 12,700 ms 100% I assume there's a lookup in the attachment table to find the attachment, then its requested from the file system. We are running on 2 load balanced servers, the app server load itself is low so I'm not sure why there would be such a lag with this function for some attachments but not all. Anyone else experience this?