"... aiming to provide performant tools ..." (1995) - https://books.google.com/books?id=uZjYdk4bQgkC&pg=PA1&dq=per...
definitions for different aspects of 'peformant' (1998) - https://books.google.se/books?id=FYkmwYKBoCwC&pg=PA235&dq=%2...
"The network and hierarchical data models, introduced in the 1960's, provide a very performant data organization for well-defined, update-intensive transaction processing of large volumes of data at the cost of conceptual complexity" (1993) - https://books.google.com/books?id=Ro3zjjTNE9UC&pg=PA327&dq=p...
Here's the n-grams trend. https://books.google.com/ngrams/graph?content=performant&yea... .
There are many domain-specific terms which have not yet made it to general dictionaries. For example, from your comments, I see you used the word 'multicast', This is not in Merriam-Webster, at http://www.merriam-webster.com/dictionary/suggestions/multic... . What makes it a word but not performant? Is "zero-copy" a word? "smarthost"? "type-punning"? "upstream"?
Software can be big or small, fast or slow, efficient or inefficient (for combinations of size and speed.) I don't think we need any more adjectives beyond those.
Instead of "significantly less performant", you could just say "much slower". (Note that LOOP was much slower on older Intel CPUs, but was the same as the longer sequence on AMD's. It would not surprise me if newer Intel ones now decode LOOP into the same sequence of uops. In any case, unless the loop is a tiny one, what happens in the body is likely to make a much more significant difference, especially if cache misses are involved.)
Some interesting reading on why LOOP was slower on Intel CPUs --- because Windows 95's timing loop used it (observe the lack of "performant" in any of those posts): https://groups.google.com/d/topic/alt.windows98/liuMAIctHRg
Also, I think performant is often used as a synonym for "fast enough", which is slightly different than "fast."
In looking around just now, economics seems to prefer the second definition, which is why I added it. All of the uses I found are compatible with this definition.
What's the definition of "object oriented" again?
For example:
- observing => observant =?= observing well (yes, exists in this meaning)
- informing => informant =?= informing well (does not exist as adjective, but could in the future?)
- thinking => thinkant =?= thinking well (does not exist at all, but could in the future?)
Scientist, doctors, lawyers, and other engineering disciplines use precise words. Software engineers should too.
As more and more people use "performant" fewer and fewer people will understand what good performance actually means. I wouldn't be surprised if this encourages a culture of wasteful premature optimization.
Languages evolve. Whether for better or worse is up to the reader. If it weren't for evolving languages, we'd all still be writing like Shakespeare.
[0]: https://en.wikipedia.org/wiki/Phonological_history_of_Englis...