Variable and Deterministic

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A virtual platform like Wind River Simics is generally designed to be deterministic. Determinism brings a host of benefits to users (repeatability of bugs, reverse execution, bug transportation, etc.), but is also easily misunderstood. Quite often, users fear that they will lose an important "feature" of a physical machine – its built-in variation across runs of the same software. If the virtual platform is deterministic, surely it will not expose all the different ways a program can run that you get on a random physical machine? Yes it can.

There is a huge difference between the repeatable determinism of a virtual machine and completely invariant, predictable, predetermined behavior.

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