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[qznc via Digitalmars-d]

On Sunday, 19 June 2016 at 10:38:27 UTC, qznc wrote:
> On Saturday, 18 June 2016 at 18:54:28 UTC, Andrei Alexandrescu 
> wrote:
>> Got this link from the reddit discussion around the blog 
>> article: http://effbot.org/zone/stringlib.htm. The 
>> Bloom-filter-style trick looks quite cool. Anyone interested 
>> in running some more experiments? Thx! -- Andrei
>
> Compare with memmem. That is 4x faster than the current stuff. 
> I guess vector instructions are key. There is a branch in my 
> repo.

More like 2x after looking again. For some more concrete numbers:

LDC:
Search in Alice in Wonderland
        std: 438 ±12
     manual: 315 ±8
   A2Phobos: 254 ±7
      Chris: 325 ±9
     Andrei: 434 ±11
    Andrei2: 259 ±6
     memmem: 100 ±0
Search in random short strings
        std: 127 ±14
     manual: 124 ±12
   A2Phobos: 107 ±8
      Chris: 130 ±15
     Andrei: 110 ±7
    Andrei2: 106 ±7
     memmem: 108 ±8
Mismatch in random long strings
        std: 534 ±432
     manual: 587 ±428
   A2Phobos: 353 ±274
      Chris: 605 ±448
     Andrei: 550 ±399
    Andrei2: 360 ±280
     memmem: 136 ±50
Search random haystack with random needle
        std: 293 ±211
     manual: 265 ±141
   A2Phobos: 212 ±163
      Chris: 271 ±133
     Andrei: 285 ±212
    Andrei2: 215 ±164
     memmem: 118 ±20
  (avg slowdown vs fastest; absolute deviation)
CPU ID: GenuineIntel Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz

DMD:
Search in Alice in Wonderland
        std: 554 ±17
     manual: 382 ±11
   A2Phobos: 346 ±10
      Chris: 501 ±18
     Andrei: 498 ±14
    Andrei2: 342 ±9
     memmem: 100 ±0
Search in random short strings
        std: 153 ±31
     manual: 131 ±19
   A2Phobos: 108 ±9
      Chris: 146 ±29
     Andrei: 109 ±10
    Andrei2: 106 ±7
     memmem: 108 ±8
Mismatch in random long strings
        std: 674 ±542
     manual: 651 ±469
   A2Phobos: 445 ±362
      Chris: 821 ±604
     Andrei: 618 ±459
    Andrei2: 436 ±354
     memmem: 134 ±50
Search random haystack with random needle
        std: 379 ±307
     manual: 284 ±175
   A2Phobos: 233 ±177
      Chris: 370 ±245
     Andrei: 299 ±238
    Andrei2: 238 ±188
     memmem: 110 ±14
  (avg slowdown vs fastest; absolute deviation)
CPU ID: GenuineIntel Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz