I recently received Debian bug report #798350 where the user had a problem with wordpress. After upgrading to version 4.3, the webservers performance degrades over time. The problem is also reported at the wordpress site with bug WordPress ticket 33423 including the fix.
I have backported the relevant changeset and uploaded Debian wordpress package 4.3+dfsg-2 which only contains this changeset. For a lot of people, including myself, you probably won’t hit this bug but if it impacts you, then try this update.