Yes, platform fragmentation is possible with different codecs used for cache. Said that, Autodesk seems not terribly worried about this possibility, as they offer a choice of cache codecs in Smoke on a Mac and on Linux. AD actually offer something, that’s even better, than the straight Prores codec. They had managed to cache each frame as a single Prores file, combining advantage of small size of Prores with frame based flexibility. This way Smoke cache can easily be played and there is no need to re-render the whole image, but just the changed frames. Yes, disk fragmentation can be a problem, but I haven’t noticed it much with my Smoke. With the new capabilities of Resolve 10 around the corner, there will be a serious need to rethink the proper use of cache for image processing. Persistent cache is just a small first step in that direction.