Welcome to TVPaint Community forums !

What's the difference between a memory defrag and an HD defrag?

I think the difference is that TVP's temp file gets disorganized with large chunks of temporary memory data being stored over and over again but all gets cleared by simply restarting TVP, but hard drive defrag happens when large chunks of data that belong together for more efficient streaming get stored into any available slots, which slows down the performance of the drive when the HD has to skip all over the place to collect the data on the fly. Defragging the HD means that the loosley stored chunks get collected back together where they can run as one piece. Geez, very layman's terms, but I believe I have this right.

Well, it's enough of an explanation for me...thanks.

there isn't really such thing as memory defrag. HD defrag exists because the spinning nature of the hard disk creates a situation in which information is written all across the surface of the disk without proper management of the bits of information. therefore a periodical defrag to the HD creates the necessary order - which gives quicker access times as the information is not needed to be sought after all across the disk. With memory it is different - it is called RAM, which stands for Random Access Memory - meaning that the information can spread randomly across the memory storage, without loosing access speed. This type of storage is much faster than hard disks, and therefore much more expensive.

In the case discussed in this thread, the possible "memory defrag" is referring probably to the erasing, or ordering, of temporary cached work files on the hard drive.
or maybe I'm talking rubbish...