Re: [reverse RFC] Add documentation for process record and replay

[Michael Snyder <msnyder at vmware dot com>]

Jakob Engblom wrote:
> > > > signals? crashes? etc.  Are there things that simply cannot be
> > > > reproduced exactly, due to fundamental limitations of the replay
> > > > target?
> > Do you have an opinion about these concerns?
>
> I would like to jump in here and point out that this will depend on the nature
> of the target.  Simics, and presumably other full-system simulation solutions,
> can replay the entire IO of a machine.  This includes any external IO that is
> asynch to the simulator execution (such as network packets and user input).
> Between machines in a simulated network of machines, replay is obviously
> perfect.
>
> If you try to do this on a live machine, it is a bit more tricky.
>
> So this is best left to the underlying mechanism, in my experience.

Absolutely.  But here, we are discussing the documentation for
one particular mechanism, what we're referring to as "process
record and replay".  This only records and replays the execution
of a single process, so it might be a good idea to document its
specific capabilities and limitations in this area.