[[Skipahead multithreading (SkMT)]] is a form of [[speculative multithreading (SpMT)]]
characterized by "skipping ahead" at certain points in
[[non-speculative or less speculative versus more speculative|non-speculative or less speculative execution to more speculative execution]].
Typically these "certain points" in thecode are places
where there is a well characterized [[control independence or convergence]] point:
* the instruction after a CALL instruction
* end of loop
* later iterations of loop
* IF convergence
I, Andy Glew, coined the term [[SkMT]]
when it became evident that the term [[SpMT]],
which was itself coined by Antonio Gonzales and promoted by me,
was more generic.
I.e. you can imagine creating speculative threads
that do not really skip that far ahead,
but which, e.g. execute past a place where execution would bee blocked,
either an in-order blockage, or where an OOO window would be full.
See [[non-skipahead speculative multithreading]].
- Oooo.... I just created a new term: [[slip-ahead multithreading]].
It rather nicely encapsulates what I just described,
and is consistent with published project names such as [[slipstream]].
In much the same way, I had earlier used the term [[implicit multithreading (IMT)]],
and replaced it by [[speculative multithreading (SpMT)]],
which I am now (after, 10 years ago, 2000) specializing to [[skipahead multithreading (SkMT)]].
The term [[skipahead]] is intended to be contrasted with [[lookahead]],
a term which was once used to characterize all [[out-of-order (OOO)]] execution.
- Look-ahead processors.
Robert M. Keller, Princeton.
ACM Computing Surveys,
Vol 7, Issue 4, Dec 1975.
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.88.5118&rep=rep1&type=pdf
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