One minor additional suggestion: if you use #:authentic for the struct, it will generate slightly better code for the accessors.
Sam On Fri, Mar 19, 2021, 6:18 AM Bogdan Popa <[email protected]> wrote: > I updated the gist with some cleanups and additional improvements that > get the runtime down to a little over 1s (vs ~350ms for the optimized C > and Rust code) on my maxed-out 2019 MBP and ~600ms on my M1 Mac Mini. > > Pawel Mosakowski writes: > > > Hi Bogdan, > > > > This is a brilliant solution and also completely over my head. It > finishes > > in ~3.75s on my PC and is faster than the Python version which basically > > delegates all the work to C. I will need to spend some time on > > understanding it but I am looking forward to learning something new. > > > > Many thanks, > > Pawel > > > > On Thursday, March 18, 2021 at 7:22:10 PM UTC bogdan wrote: > > > >> I managed to get it about as fast as Python by making it really > >> imperative and rolling my own hash: > >> > >> https://gist.github.com/Bogdanp/fb39d202037cdaadd55dae3d45737571 > >> > >> Sam Tobin-Hochstadt writes: > >> > >> > Here are several variants of the code: > >> > https://gist.github.com/d6fbe3757c462d5b4d1d9393b72f9ab9 > >> > > >> > The enabled version is about the fastest I can get without using > >> > `unsafe` (which the rules said not to do). It's possible to optimize a > >> > tiny bit more by avoiding sorting, but only a few milliseconds -- it > >> > would be more significant if there were more different words. > >> > > >> > Switching to bytes works correctly for the given task, but wouldn't > >> > always work in the case of general UTF8 input. But those versions > >> > appeared not be faster for me. Also, writing my own string-downcase > >> > didn't help. And using a big buffer and doing my own newline splitting > >> > didn't help either. > >> > > >> > The version using just a regexp matching on a port (suggested by > >> > Robby) turned out not to be faster either, so my suspicion is that the > >> > original slowness is just using regexps for splitting words. > >> > > >> > Sam > >> > > >> > On Thu, Mar 18, 2021 at 11:28 AM Sam Tobin-Hochstadt > >> > <[email protected]> wrote: > >> >> > >> >> Here's a somewhat-optimized version of the code: > >> >> > >> >> #lang racket/base > >> >> (require racket/string racket/vector racket/port) > >> >> > >> >> (define h (make-hash)) > >> >> > >> >> (time > >> >> (for* ([l (in-lines)] > >> >> [w (in-list (string-split l))] > >> >> [w* (in-value (string-downcase w))]) > >> >> (hash-update! h w* add1 0))) > >> >> > >> >> (define v > >> >> (time > >> >> (for/vector #:length (hash-count h) > >> >> ([(k v) (in-hash h)]) > >> >> (cons k v)))) > >> >> (time (vector-sort! v > #:key cdr)) > >> >> (define p (current-output-port) #;(open-output-nowhere)) > >> >> (time > >> >> (for ([pair (in-vector v)]) > >> >> (write-string (car pair) p) > >> >> (write-string (number->string (cdr pair)) p) > >> >> (newline p))) > >> >> > >> >> It's much more imperative, but also pretty nice and compact. The > >> >> `printf` optimization is significant for that portion of the program, > >> >> but that isn't much of the running time. The overall running time for > >> >> 10 copies of the KJV is about 9 seconds on my laptop. > >> >> > >> >> I think the remaining difference between Racket and other languages > is > >> >> likely the `string-split` and `string-downcase` functions, plus the > >> >> relatively-inefficient string representation that Racket uses. > >> >> > >> >> Sam > >> >> > >> >> > >> >> On Thu, Mar 18, 2021 at 10:28 AM Pawel Mosakowski < > [email protected]> > >> wrote: > >> >> > > >> >> > Hi David, > >> >> > > >> >> > Yes, the 21 seconds includes the interpreter startup time. I have > >> done a simple test to see how long it takes: > >> >> > > >> >> > $ time racket -e '(displayln "Hello, world")' > >> >> > Hello, world > >> >> > > >> >> > real 0m0.479s > >> >> > user 0m0.449s > >> >> > sys 0m0.030s > >> >> > > >> >> > I have also put my code inside a main function and profiled it: > >> >> > > >> >> > Profiling results > >> >> > ----------------- > >> >> > Total cpu time observed: 20910ms (out of 20970ms) > >> >> > Number of samples taken: 382 (once every 55ms) > >> >> > (Hiding functions with self<1.0% and local<2.0%: 1 of 12 hidden) > >> >> > > >> >> > ============================================================== > >> >> > Caller > >> >> > Idx Total Self Name+src Local% > >> >> > ms(pct) ms(pct) Callee > >> >> > ============================================================== > >> >> > [1] 20910(100.0%) 0(0.0%) [running body] > >> ...word-occurences-profile.rkt":##f > >> >> > profile-thunk [2] 100.0% > >> >> > -------------------------------------------------------------- > >> >> > [running body] [1] 100.0% > >> >> > [2] 20910(100.0%) 0(0.0%) profile-thunk > >> ...ket/pkgs/profile-lib/main.rkt:9:0 > >> >> > run [3] 100.0% > >> >> > -------------------------------------------------------------- > >> >> > profile-thunk [2] 100.0% > >> >> > [3] 20910(100.0%) 0(0.0%) run > >> ...share/racket/pkgs/profile-lib/main.rkt:39:2 > >> >> > main [4] 100.0% > >> >> > -------------------------------------------------------------- > >> >> > run [3] 100.0% > >> >> > [4] 20910(100.0%) 50(0.2%) main > >> ...cket/count-word-occurences-profile.rkt:5:0 > >> >> > read-from-stdin-it [5] 98.5% > >> >> > ??? [6] 0.2% > >> >> > -------------------------------------------------------------- > >> >> > main [4] 100.0% > >> >> > [5] 20606(98.5%) 11796(56.4%) read-from-stdin-it > >> ...-occurences-profile.rkt:19:6 > >> >> > internal-split [7] 42.8% > >> >> > -------------------------------------------------------------- > >> >> > main [4] 100.0% > >> >> > [6] 51(0.2%) 0(0.0%) ??? > >> ...cket/collects/racket/private/sort.rkt:369:3 > >> >> > generic-sort/key [8] 100.0% > >> >> > -------------------------------------------------------------- > >> >> > read-from-stdin-it [5]100.0% > >> >> > [7] 8810(42.1%) 3528(16.9%) internal-split > >> ...collects/racket/string.rkt:117:0 > >> >> > regexp-split [9] 59.9% > >> >> > -------------------------------------------------------------- > >> >> > ??? [6] 100.0% > >> >> > [8] 51(0.2%) 0(0.0%) generic-sort/key > >> .../racket/private/sort.rkt:156:2 > >> >> > copying-mergesort [10]100.0% > >> >> > -------------------------------------------------------------- > >> >> > internal-split [7] 100.0% > >> >> > [9] 5282(25.3%) 2810(13.4%) regexp-split > >> ...ts/racket/private/string.rkt:338:2 > >> >> > loop [11] 46.8% > >> >> > -------------------------------------------------------------- > >> >> > generic-sort/key [8] 10.0% > >> >> > copying-mergesort [10] 90.0% > >> >> > [10] 51(0.2%) 51(0.2%) copying-mergesort > >> ...racket/private/sort.rkt:129:8 > >> >> > copying-mergesort [10] 90.0% > >> >> > -------------------------------------------------------------- > >> >> > regexp-split [9] 100.0% > >> >> > [11] 2471(11.8%) 2471(11.8%) loop > >> ...t/collects/racket/private/string.rkt:169:7 > >> >> > -------------------------------------------------------------- > >> >> > > >> >> > Kind regards, > >> >> > Pawel > >> >> > > >> >> > > >> >> > On Thursday, March 18, 2021 at 2:09:35 PM UTC [email protected] > >> wrote: > >> >> >> > >> >> >> Hi Pawel, > >> >> >> > >> >> >> I'll take a look at the code later, but did that 21 seconds > include > >> startup time for the interpreter? > >> >> >> > >> >> >> On Thu, Mar 18, 2021, 9:24 AM Pawel Mosakowski < > [email protected]> > >> wrote: > >> >> >>> > >> >> >>> Hello, > >> >> >>> > >> >> >>> I am a Racket beginner and I have come across this article: > >> >> >>> > >> >> >>> https://benhoyt.com/writings/count-words/ > >> >> >>> > >> >> >>> This is my attempt at solving the challenge: > >> >> >>> > >> >> >>> https://pastebin.com/kL16w5Hc > >> >> >>> > >> >> >>> However when I have benchmarked it, it takes ~21 seconds to run > >> compared to the Python and Ruby versions which take around 3-4 seconds. > >> >> >>> > >> >> >>> I understand that both Ruby and Python probably have the string > >> operations and hash tables implemented in optimized C but is there > anything > >> I can do to improve performance of my program? > >> >> >>> > >> >> >>> Many thanks for all help and suggestions. > >> >> >>> > >> >> >>> -- > >> >> >>> 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/118c1340-66d1-421d-92a4-6b66c56cb88fn%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/09c58a34-bd2d-49e7-bfbd-d3253c1e6dd1n%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/m2r1kb30qh.fsf%40192.168.0.142 > . > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. 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