Re: How to stl library efficiently?

From:
"Sergey P. Derevyago" <non-existent@iobox.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Wed, 13 Aug 2008 12:24:41 CST
Message-ID:
<48a298d9$0$90276$14726298@news.sunsite.dk>
Peng Yu wrote:

I'm wondering whether are less obvious tricks to make stl based
program performance as good as the hard coded C program?

    
Sure.

    Please read "C++ multithreading: mem_pool" message:
Message-ID: <4899c3e1$0$90276$14726298@news.sunsite.dk>
http://groups.google.com/group/comp.programming.threads/msg/b52ce202a371778b

-----------------------------------8<-----------------------------------
void start_std(void*)
{
  list<int> lst;
  for (int i=0; i<N; i++) {
      for (int j=0; j<M; j++) lst.push_back(j);
      for (int j=0; j<M; j++) lst.pop_front();
  }
}
void start_ders(void*)
{
  mem_pool mp;
  stl_allocator<int> alloc(mp);

  list<int, stl_allocator<int> > lst(alloc);
  for (int i=0; i<N; i++) {
      for (int j=0; j<M; j++) lst.push_back(j);
      for (int j=0; j<M; j++) lst.pop_front();
  }
}
-----------------------------------8<-----------------------------------
The table at http://ders.stml.net/cpp/mtprog/mtprog.html#3.1.1 shows
that start_ders() function is tens and hundreds (!!!) of times faster:
1 CPU : 38.1
1 CPU,HT : 42.1
2 CPU,SMP: 321.6 (!!!)
2 CPU,HT : 37.0
--
          With all respect, Sergey. http://ders.stml.net/
          mailto : ders at skeptik.net

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