High traffic to /rest/quickreload/ endpoint after upgrading to Confluence 5
Problem
After upgrading to Confluence 5, you may notice additional traffic if your instance is publicly accessible to anonymous users.
You may notice the following or similar in your access logs:
xxx.xxx.xxx.xx - [25/Mar/2014:00:00:04 +0000] "GET /rest/quickreload/latest/xxx HTTP/1.1" 200 46 "http://confluence.example.com/display/DS/Home" "Mozilla/5.0 (X11; Linux x86_64; rv:30.0) Gecko/20100101 Firefox/30.0" UserID:"-"
While there is nothing unusual about the request itself, you may see a great deal of requests (anonymous or otherwise) the the URL shown above - /rest/quickreload/.
Cause
Confluence 5.0+ introduced a Quick Reload plugin. The Quick Reload plugin lets a user know if new comments have been added to the page that they're on. This functionality is exposed as a REST endpoint that can be called by JavaScript without reloading the current page. If your Confluence instance is receiving a lot of anonymous traffic, you may be seeing extra load generated by the QuickReload plugin.
You should only use the workarounds in this document if your Confluence instance is suffering from severe performance degradation. If in doubt, contact support.
Workaround 1
If you're using Apache as a reverse proxy in front of your Confluence instance, you may be able to reduce the load by blocking traffic to the endpoint by using the ProxyBlock directive.
Workaround 2
Disable the Quick Reload plugin.
By disabling the Quick Reload Plugin, users will no longer see a popup notification on the page they are viewing when new comments are added to that page. They will still receive all configured email and workbox notifications.
Load on your Confluence instance will not decrease immediately after disabling the plugin, because users will often receive cached copies of the page. Cached copies of pages will still attempt to request the /rest/quickreload/ endpoint, which will result in a 404 error. As the content in caches expires, you will see less 404 errors on this URL. The 404 page that is generated is a larger file than the normal response generated by the /rest/quickreload/ endpoint - so load may actually increase on the server.
To Disable the Quick Reload Plugin:
Choose the cog icon at the top right of the screen, then choose "Add-Ons"
From the drop down menu showing "User-installed" select "System"
Scroll down to find "Confluence Quick Reload Plugin" and click on it
Click "Disable"