From memory rr has a substantive recording overhead, and is specially made for debugging, right? But yes it is very useful to analyse a past state and to unders

From memory rr has a substantive recording overhead, and is specially made for debugging, right? But yes it is very useful to analyse a past state and to understand a chain of events. I should clarify my use case: I would use such a feature (go back to previous state) for a speculative execution tool. I'd execute the happy path all the time assuming no error occured, but if I found out later that something went wrong somewhere, I'd want to go back and start from there knowing what went wrong, and so on. With as little perf loss as possible. Not sure my explanation makes sense. I know about dmtcp, criu, vm snapshots, but they all come with big overhead (I don't want to pay too much for the checkpoint). The closest I found was @gamozolabs amazing work on snapshot fuzzing (pushing the limit of what's possible on x86_64 hardware, including using Intel PML - similar to userfaultfd but hw-accelerated...).