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Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)"

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Bonita Montero <Bonita.Montero@gmail.com> writes:
>>> Problem is that if binary tree is not reorganizing internaly to be cache
>>> friendly for every insert (balancing and making close nodes close to
>>> each other) traversing set is awfully slow.
>
>> A vector isn't cache-friendly either when you do a binary search.
>> Random-access memory-accesses are always slow.
>
>I just wrote a little test:
>
>#include <iostream>
>#include <set>
>#include <vector>
>#include <algorithm>
>#include <random>
>#include <chrono>
>
>using namespace std;
>using namespace chrono;
>
>int main()
>{
>	using hrc_tp = time_point<high_resolution_clock>;
>	size_t const ROUNDS = 10'000'000;
>	set<int> si;
>	for( int i = 1000; --i; )
>		si.insert( i );

A thousand integers will fit in the L1 cache.  Try
it with a hundred million.

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Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Juha Nieminen <nospam@thanks.invalid> - 2021-05-28 06:45 +0000
  Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-05-28 17:05 +0000
    Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-28 19:31 +0200
      Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-28 19:54 +0200
        Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" scott@slp53.sl.home (Scott Lurndal) - 2021-05-28 20:20 +0000
          Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-29 05:18 +0200
        Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-05-28 21:50 +0000
          Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-29 05:25 +0200
            Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-29 05:42 +0200
            Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-05-29 10:44 +0000
              Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-29 13:00 +0200
        Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-29 02:24 +0300
      Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-05-28 21:31 +0000
      Re: "STL: Amazing Speed Differences between std::vector and std::set (Observed with an UndoRedoAction)" Juha Nieminen <nospam@thanks.invalid> - 2021-05-30 06:40 +0000

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