[YorkianTones]

Windows has had this capability for at least 8 years with "time travel tracing" (or iDNA tracing), which produces a dump file that can be traversed back and forward in WinDBG or Visual Studio. Very useful for figuring out what caused unexpected state in complex integration scenarios with timing-dependent bugs. http://www.thewindowsclub.com/microsoft-time-travel-tracing-...

[moyix]

iDNA traces are huge though, and recording them adds a ton of overhead. rr is way more lightweight.

[necessity]

It's called trace/execution replay and has been around for decades in various platforms, not just Windows.