if you want to look at checkpointing, it's worth going back to look at Condor, because they made it really work. There are a few interesting issues that you need to get right. You can't make it 50% of the way there; that's not useful. You have to hit all the bits -- open /tmp files, sockets, all of it. It's easy to get about 90% of it but the last bits are a real headache. Nothing that's come along since has really done the job (although various efforts claim to, you have to read the fine print).
ron
