In this context, Rust's semantics do allow C-level performance- they make it straightforward to describe the same machine code that C would. In some cases, they even enable more compiler optimizations than C does.
Java, on the other hand, makes it hard or impossible to do that (straightforwardly at least). A more mature compiler will make a lot of difference- compare early Java performance to where it is now, for example.
Please share your measurements of "real-world performance" that are "not very correlated" with the benchmarks game's results.
edit: Please provide a better response than downmods.
edit: Please provide a better response than downmods.
Just a URL to published comparison measurements would be so much more interesting for anyone interested in Rust, than downmods.
(There seem to have been plenty of breaking language changes in the last 6 months.)
(The "faster" bit isn't important; various reasons might have made C++ slower than Rust for this, but what is important is that perf was comparable)
What I questioned was Rusky's technical-sounding but apparently unsupported claim that "the benchmarks game's results are not very correlated with real-world performance." For Rusky to know he'd need some kind-of "real-world performance" measurements and a correlation coefficient - neither of which have been shown.
I'm working on improving the regex engine now. Hopefully I can submit some improvements soon. :-) It will be hard to get near the top, but I think there's some low hanging fruit I can tackle first.
A couple of weeks ago you said -- "… optimizing performance hasn't been a focus, shipping good language semantics has been."
https://news.ycombinator.com/item?id=9565405
edit: Please provide a better response than downmods.
Optimizing the workloads tested on the benchmarks game has not been a focus.
https://news.ycombinator.com/item?id=9554676
edit: Please provide a better response than downmods.
It isn't bad manners to trust that when steveklabnik answers "No, as optimizing performance hasn't been a focus, shipping good language semantics has been." that's what he means.
Conclusion: Don't draw conclusions from the benchmarks game.
[1] http://benchmarksgame.alioth.debian.org/u64q/performance.php...
[2] i5-3470 @ 3.20GHz
the answer was to what qualities make a lang suited for systems programming not just specific to Rust