I have my AE disk cache enabled and set up slightly higher than the default 2000 MB. I have it set to 10000 MB. One would think that once the cache reached the max level of 10000, that it would dump old cache to stay under the 10000. However, the disk cache is ballooning out of control and never dumps. It eats up my entire 500GB hard drive with cache and does so rather quicly, then my render crashes. This happened on my boot drive and practically locked up my entire system because there was no HD space left. I've since set the disk cache to another internal drive, but it doesn the same thing. Short of turning off disk cache completley am I missing something here or is this yet another bug?
The disk cache should not show this behavior and it doesn't on my systems. Only the media cache is persistent and needs to be cleaned from time to time. if it occurs during rendering, it would also not make sense for the program to use the disk cache. What you are perhaps seeing is the program duplicating/ copying specific files when using MP rendering, which can happen if you use formats that do not allow concurrent access to the same source file. That may also include formats handled by the media cache and often extends to specific CoDecs that require to save temporary frames before appending thme to movie clips. In any case, the behavior you see could be normal, but could also be wrong, whichever way the gravity works... I recommend you keep an eye on the things I mentioned and try to limit risk factors by testing without MP, using different formats etc.