As of iOS 5.0 Apple began to purge or clean the Caches directory inside individual applications when it decided the device was using too much space. Can anyone point me to the location of documentation or anecdotal information regarding at which threshold this cache cleaning occurs (for instance 90%+ disk usage) and how often it is checked?
as far as i know there hasn't been any official information about when the purge happens and - to be honest - you shouldn't be trying to predict it. it IS a problem, though. thankfully, apple has realised this and as of iOS 5.0.1 you can set a "do not backup" flag:
ReplyDeletehttp://developer.apple.com/library/ios/#qa/qa1719/_index.html
so you'll want to place those files in your app's Documents/ dir or your apps Library/Private Documents/ and set the "do not backup" attribute.