How does a historical debugger work?

Question

The historical debugger is able to return the program state (including the current instruction) to its previous state. How is this possible in managed or unmanaged environments? I can not imagine that the debugger removes the state of the entire system from each command.

Answer 1

One way to do this is to record the sources of non-determinism in the system (I / O, interrupts) and take snapshots of the states at different intervals. Thus, you can “rewind” by restoring the previous picture and playing forward using recorded non-determinism until you click the desired item in the past.

For example, imagine this timeline:

1    2           3     4
|    |           |     |

• Program launch
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Answer 2

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Answer 3

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