With the recent improvements by Phil, the rank of the syntax object variant moves up from 26th to the second (what?!?), losing only to c++ / g++. Moreover, it's significantly faster than the third place.
On Fri, Mar 5, 2021 at 3:29 AM [email protected] < [email protected]> wrote: > Oh I see. So one problem is here that `match-define` expands to `match` > with an implicit error case, which at the low level, isn't distinguished > from a user-written second case, and the tag check can't just be eliminated. > > On Thursday, March 4, 2021 at 9:40:22 AM UTC-8 Sam Tobin-Hochstadt wrote: > >> I think there are two reasons that code gets slower. >> >> 1. The `match-define` includes pair and struct checks, which are >> omitted for plain accessor uses because of the unsafe declaration. >> 2. That use of `match` expands to `define-values` which ends up as a >> `call-with-values` and a `case-lambda` at the chez layer and is not >> removed. >> >> `match` could recognize that it's being compiled with unsafe mode and >> omit these checks, although it's not that straightforward. Also >> schemify (or Chez) could do more to eliminate the use of multiple >> values, although that's hard without eliminating the failure cases. >> >> Sam >> >> On Thu, Mar 4, 2021 at 3:23 AM [email protected] >> <[email protected]> wrote: >> > >> > Thanks for the tip about PLT_CS_COMPILE_LIMIT! I submitted a revision >> to the syntax object variant that incorporated sleepnova's and yjqww6's >> improvements. >> > >> > Also, I never knew about `(#%declare #:unsafe)` until I saw yjqww6's >> pull request. It makes a noticeable difference. One unsatisfying thing is >> that in one place, if I replace the 4 separate define clauses with just >> `(match-define (cons (op o val) rst) parsed)`, the benchmarks are more than >> twice slower. >> > >> > On Wednesday, March 3, 2021 at 11:12:30 AM UTC-8 Sam Tobin-Hochstadt >> wrote: >> >> >> >> First, there's no longer a difference because yjqww6 just had a PR >> >> merged that improves the Racket performance. >> >> >> >> The performance difference that was there was mostly because the Chez >> >> code was run with `--optimize-level 3` which turns off safety. If that >> >> was changed to `--optimize-level 2` the timing became much slower. >> >> >> >> Sam >> >> >> >> On Mon, Mar 1, 2021 at 2:39 AM [email protected] >> >> <[email protected]> wrote: >> >> > >> >> > There’s this benchmark on BF interpreter where the Racket and Chez >> Scheme implementations are very similar, but Chez Scheme is much faster >> than Racket 8.0 at interpreting bench.b (3s vs 8s) and mandel.b (40s vs >> 136s). >> >> > >> >> > There’s the “Racket (Syntax Object)” variant that directly parses >> BF’s syntax into Racket syntax object, which is faster (3.7s for bench, 82s >> for mandel), but still significantly behind Chez Scheme’s naive >> interpreter. >> >> > >> >> > Profiling doesn’t give very illuminating results, saying most of the >> cost is from interpreting BF’s loop instruction. >> >> > >> >> > Given that Racket is on Chez, could this benchmark reveal some low >> hanging fruit for improving Racket’s performance? >> >> > >> >> > -- >> >> > You received this message because you are subscribed to the Google >> Groups "Racket Users" group. >> >> > To unsubscribe from this group and stop receiving emails from it, >> send an email to [email protected]. >> >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/racket-users/83b2819d-8295-4769-944d-fa0c155976dan%40googlegroups.com. >> >> > >> > -- >> > You received this message because you are subscribed to the Google >> Groups "Racket Users" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> an email to [email protected]. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/racket-users/a5e77286-68b8-481a-8dea-0f547c5ce968n%40googlegroups.com. >> >> > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/racket-users/f771a13a-9fc4-4b71-9e47-3a83eb5290e7n%40googlegroups.com > <https://groups.google.com/d/msgid/racket-users/f771a13a-9fc4-4b71-9e47-3a83eb5290e7n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/CADcuegvSFZvD9SaTz2uakJp%3D6tmoEmVbGJKhxwzdeHsse8jVkQ%40mail.gmail.com.
