Just reporting this experience with Blender 2.57.
I am working at a client site using their hardware and network. Files for specific projects are required to remain on certain hard drives that are shared through out the network.
So I have a fast local machine, but it needs to connect through the network to open a file. The network is pretty fast and I can see all my linked image assets displayed in Blender just fine.
HOWEVER, whenever I issue an undo command, there is a significant wait and I get a spinning beachball on OSX 10.5.8 while Blender processes the undo.
My guess is that Blender is fetching or storing some kind of undo file on the network drive instead of the local drive, which would give better performance.
I can understand the concept of keeping the undo file in the same location as the project BLEND file, but in this case, poor performance is the result.
I am wondering if it would be possible to change the way this works so undo through the network is not so slow?