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by Veserv 840 days ago
No, time travel debugging is almost certainly a root, but comes from a different lineage.

https://jakob.engbloms.se/archives/1564

The Green Hills Software Time Machine product for time travel debugging was commercially available by September 2003 [1] which is at least contemporaneous with that paper by Bill Lewis (i.e. terminology could not have been derived from it).

Given the alternative terminology frequently used for the technology up to and after that point such as bidirectional, reverse, reversible, omniscient, replay, record-replay, etc. time-travel debugging as a term almost certainly originates/was popularized by Time Machine as the first successful time travel product (yes, I see the Lauterbach CTS is listed as existing first, but it was not commercially distinguished and successful and obviously has no terminology lineage).

[1] https://www.ghs.com/news/20030930_best_of_show.html
1 comments
roca 840 days ago
There's a clear difference between "omniscient" debugging and "time travel" debugging. The latter almost always refers to debuggers that let you move backwards in time but only let you access state at the "current point in time", and moving forward or backward has a noticeable cost. Omniscient debuggers (e.g. Pernosco or Lewis' work) give you approximately instant access to states at different points in time.
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Veserv 840 days ago
No, what you call “omniscient debugging” is what Time Machine does and has always done. Instant temporal random access, call stacks over time with click to seek, variable graphing over time, etc. Given that is almost certainly where “time-travel debugging” came from, that seems more like people copying it poorly and watering down the phrase.

Unless you mean something really narrow like clicking a variable and it showing you every previous value of it in one screen? I am not sure if it has that built-in. But really that is just visualization layer stuff. The recorded log has everything you need to reconstruct every past state, so you can get anything missing from the built-ins by just querying the log directly.

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