Mp3tag says it supports unlimited undo feature. How does that work? Anybody familiar to that?
In terms of resource, there are two ways...
2) HDD/SDD etc. storage
If you change 100,000 photos in one operation, that is quite some resource penalty.
Often, a hybrid of both are implemented. So after say x number of operations, the rest are saved to a more permanent storage e.g. db.
mp3tag is a tool that is loaded, used and then closed, therefore, the used resource is quickly recovered. Conversely, MB is often minimised, therefore, such a hit on resource is a certain consideration. Saying that, I am not likely to change 100,000 photos, but I am thinking of the community use rather than my own.
There are many +1s so @Steven if you do implement this feature, can you add a configurable limit on the impact this has on resources (say a max of 10 undo steps by default) Then watch people later complain and wonder how MB is using 1 Gb ram.