What's the difference with RR?
Free Windows equivalent: WinDbg Time Travel Debugging (https://learn.microsoft.com/en-gb/windows-hardware/drivers/d...).
gdb should already have a similar feature?
if you could get this working on embedded arm cpus, I think you'd be surprised how many customers there would be.
Let me save you a click:
Pricing & Licensing
A UDB floating license costs $7,900 per year.
Another more powerful option: Intel SDE / PinPlay
FOSS alternative: https://rr-project.org/