Re: How do the malloc() and free() algorithms work?

Newsgroups	comp.lang.c
Date	2017-05-16 15:00 -0700
References	<733ff530-fc43-46a2-88b1-b3b25c50ac49@googlegroups.com> <eb502f48-2399-4170-9884-23ff23435bc9@googlegroups.com>
Message-ID	<98771b35-6340-4e7d-a1ef-e421ad5bb653@googlegroups.com> (permalink)
Subject	Re: How do the malloc() and free() algorithms work?
From	supercat@casperkitty.com

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On Tuesday, May 16, 2017 at 4:02:30 PM UTC-5, Rick C. Hodgin wrote:
> I ask because I've written one that is performing 3x to 8x faster than MSVC++'s,
> and I can't believe it.  I am thinking I am doing something wrong.

It's possible to optimize memory management code around different usage
patterns.  Code which is optimized for the usage patterns that are
actually encountered may be able to perform much faster than code which
is not.  In the era when the first versions of MSVC were created, heavy
use of malloc() and free() was practically an admission that one wasn't
interested in performance, since programs with memory management code
tailored to its actual needs could vastly outperform functions that had
to accommodate arbitrary sequences of acquisitions and releases.

Thread

How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-16 12:39 -0700
  How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-16 14:02 -0700
    Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-05-16 15:00 -0700
      Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-16 17:56 -0700
        Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-05-17 07:56 -0700
    Re: How do the malloc() and free() algorithms work? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-05-16 15:15 -0700
  Re: How do the malloc() and free() algorithms work? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-05-16 15:06 -0700
  Re: How do the malloc() and free() algorithms work? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-05-16 15:13 -0700
  Re: How do the malloc() and free() algorithms work? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-05-16 15:45 -0700
  Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-05-16 22:31 -0500
  Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-17 07:22 -0700
  Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-17 09:15 -0700
    Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-05-17 10:35 -0700
    Re: How do the malloc() and free() algorithms work? bartc <bc@freeuk.com> - 2017-05-19 12:17 +0100
      Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-19 04:56 -0700
      Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-19 16:05 -0700
        Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-30 14:08 -0700
          Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-07-29 09:47 -0700
  Re: How do the malloc() and free() algorithms work? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2017-05-18 20:48 +0800
    Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-18 07:19 -0700
      Re: How do the malloc() and free() algorithms work? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-05-18 07:33 -0700
        Re: How do the malloc() and free() algorithms work? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2017-05-18 23:32 +0800
          Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-18 08:45 -0700
            Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-18 08:47 -0700
        Re: How do the malloc() and free() algorithms work? Keith Thompson <kst-u@mib.org> - 2017-05-18 09:24 -0700
          Re: How do the malloc() and free() algorithms work? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-05-18 12:18 -0700
            Re: How do the malloc() and free() algorithms work? asetofsymbols@gmail.com - 2017-05-19 14:37 -0700
              Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-05-19 16:01 -0600
                Re: How do the malloc() and free() algorithms work? asetofsymbols@gmail.com - 2017-05-31 00:05 -0700
                Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-05-31 10:11 -0600
                Re: How do the malloc() and free() algorithms work? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-05-31 09:20 -0700
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-05-31 13:03 -0400
                Re: How do the malloc() and free() algorithms work? David Kleinecke <dkleinecke@gmail.com> - 2017-05-31 12:14 -0700
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-05-31 16:11 -0400
                Re: How do the malloc() and free() algorithms work? David Kleinecke <dkleinecke@gmail.com> - 2017-05-31 20:23 -0700
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-06-01 11:13 -0400
                Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-05-31 21:50 -0600
                Re: How do the malloc() and free() algorithms work? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-01 11:28 +0100
                Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-06-01 07:40 -0700
                Re: How do the malloc() and free() algorithms work? scott@slp53.sl.home (Scott Lurndal) - 2017-06-01 15:36 +0000
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-06-01 11:14 -0400
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-01 11:36 -0500
                Re: How do the malloc() and free() algorithms work? gordonb.zj91o@burditt.org (Gordon Burditt) - 2017-06-05 01:11 -0500
                Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-06-05 08:01 -0700
                Re: How do the malloc() and free() algorithms work?  gordonb.gl67j@burditt.org (Gordon Burditt) - 2017-06-05 23:49 -0500
                Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-06-06 10:13 -0700
                Re: How do the malloc() and free() algorithms work? David Kleinecke <dkleinecke@gmail.com> - 2017-06-06 16:50 -0700
                Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-06-06 21:33 -0600
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-07 00:37 -0500
                Re: How do the malloc() and free() algorithms work? David Kleinecke <dkleinecke@gmail.com> - 2017-06-07 17:13 -0700
                Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-06-07 21:35 -0600
                Re: How do the malloc() and free() algorithms work? David Kleinecke <dkleinecke@gmail.com> - 2017-06-07 22:06 -0700
                Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-06-13 08:45 -0600
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-06-08 08:36 -0400
                Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-06-08 07:51 -0700
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-06-08 11:19 -0400
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-08 11:39 -0500
                Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-06-08 10:39 -0700
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-06-08 14:01 -0400
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-08 13:06 -0500
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-08 13:18 -0500
                Re: How do the malloc() and free() algorithms work? scott@slp53.sl.home (Scott Lurndal) - 2017-06-08 18:33 +0000
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-08 14:21 -0500
                Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-06-13 10:37 -0700
                Re: How do the malloc() and free() algorithms work? scott@slp53.sl.home (Scott Lurndal) - 2017-06-13 18:08 +0000
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-14 20:15 -0500
                Re: How do the malloc() and free() algorithms work? scott@slp53.sl.home (Scott Lurndal) - 2017-06-08 15:44 +0000
                Re: How do the malloc() and free() algorithms work? David Kleinecke <dkleinecke@gmail.com> - 2017-06-08 11:34 -0700
                Re: How do the malloc() and free() algorithms work? scott@slp53.sl.home (Scott Lurndal) - 2017-06-08 12:52 +0000
                Re: How do the malloc() and free() algorithms work? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-08 10:48 -0500
                Re: How do the malloc() and free() algorithms work? asetofsymbols@gmail.com - 2017-05-31 13:10 -0700
                Re: How do the malloc() and free() algorithms work? Jerry Stuckle <jstucklex@attglobal.net> - 2017-05-31 16:12 -0400
                Re: How do the malloc() and free() algorithms work? asetofsymbols@gmail.com - 2017-05-31 13:25 -0700
                Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-05-31 21:51 -0600
                Re: How do the malloc() and free() algorithms work? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-05-31 21:05 -0700
      Re: How do the malloc() and free() algorithms work? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2017-05-18 23:28 +0800
        Re: How do the malloc() and free() algorithms work? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-05-18 08:42 -0700
        Re: How do the malloc() and free() algorithms work? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-05-18 09:46 -0600
        Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-05-18 09:08 -0700
          Re: How do the malloc() and free() algorithms work? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-05-18 15:48 -0700
            Re: How do the malloc() and free() algorithms work? supercat@casperkitty.com - 2017-05-18 16:07 -0700
              Re: How do the malloc() and free() algorithms work? "Chris M. Thomasson" <invalid@invalid.invalid> - 2017-05-20 15:17 -0700
  Re: How do the malloc() and free() algorithms work? Siri Cruise <chine.bleu@yahoo.com> - 2017-05-20 16:06 -0700

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