Re: Malloc Query

From	cri@tiac.net (Richard Harter)
Newsgroups	comp.lang.c
Subject	Re: Malloc Query
Date	2011-05-18 19:31 +0000
Message-ID	<4dd41ca1.615874038@text.giganews.com> (permalink)
References	<iquit3$pl$1@speranza.aioe.org> <87aael3xw1.fsf@blp.benpfaff.org> <ir096a$6vd$1@dont-email.me>

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On Wed, 18 May 2011 12:05:20 +0100, "BartC" <bc@freeuk.com> wrote:

>
>
>"Ben Pfaff" <blp@cs.stanford.edu> wrote in message 
>news:87aael3xw1.fsf@blp.benpfaff.org...
>> Pushpa <pushpa@nospam.invalid> writes:
>>
>>> Many users claim that malloc() and free() provided by the language
>>> library results in considerable
>>> amount of overhead in terms of calling the same. Can we really
>>> eliminate overhead by using
>>> used defined functions/user defined memory manager. Is there any
>>> significant advantage in providing user defined malloc() and
>>> free().
>>
>> According to an academic study I read some time ago, there is
>> rarely any significant advantage to special-purpose memory
>> allocators.  In a quick online search, I didn't find a reference
>> to this paper, but perhaps someone else here has a copy of it.
>
>I've just done a test where allocating and freeing large numbers of 4-byte 
>blocks took twenty times longer using malloc/free (and probably took 2-4 
>times as much space) than using a special allocator.
>
>How significant this is depends on the application, but I don't think you 
>can just dismiss such an allocator.

That sounds rather odd thing to do, since on many machines the block
addresses would be as large as the block.

Thread

Malloc Query Pushpa <pushpa@nospam.invalid> - 2011-05-17 19:39 +0000
  Re: Malloc Query blp@cs.stanford.edu (Ben Pfaff) - 2011-05-17 12:55 -0700
    Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 12:05 +0100
      Re: Malloc Query Pushpa <pushpa@nospam.invalid> - 2011-05-18 17:11 +0000
        Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 22:42 +0100
        Re: Malloc Query Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-18 21:10 -0400
      Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-18 19:34 +0100
        Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-18 17:10 -0400
          Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 00:26 +0100
            Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-18 21:25 -0400
              Re: Malloc Query James Kuyper <jameskuyper@verizon.net> - 2011-05-18 21:38 -0400
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 14:11 -0400
                Re: Malloc Query James Kuyper <jameskuyper@verizon.net> - 2011-05-19 22:55 -0400
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-20 12:14 -0400
              Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 03:22 +0100
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 14:20 -0400
                Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 23:51 +0100
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 20:01 -0400
                Re: Malloc Query luser- -droog <mijoryx@yahoo.com> - 2011-05-22 02:49 -0700
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 10:46 -0400
                Re: Malloc Query Shao Miller <sha0.miller@gmail.com> - 2011-05-22 12:37 -0500
                Re: Malloc Query Shao Miller <sha0.miller@gmail.com> - 2011-05-22 13:02 -0500
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 14:12 -0400
                Re: Malloc Query Shao Miller <sha0.miller@gmail.com> - 2011-05-23 03:06 -0500
                Re: Malloc Query luser- -droog <mijoryx@yahoo.com> - 2011-05-23 00:42 -0700
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 11:10 -0400
                Re: Malloc Query Keith Thompson <kst-u@mib.org> - 2011-05-23 09:06 -0700
                Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-22 23:18 +0100
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 19:18 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-23 11:22 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 01:57 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-23 19:24 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 14:20 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 07:41 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 16:24 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 09:20 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 18:05 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 10:37 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 19:34 -0400
                Re: Malloc Query "robertwessel2@yahoo.com" <robertwessel2@yahoo.com> - 2011-05-23 17:48 -0700
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-24 12:56 +1200
                Re: Malloc Query James Kuyper <jameskuyper@verizon.net> - 2011-05-24 07:19 -0400
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-24 11:32 -0400
                Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-23 01:04 +0100
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 02:36 -0400
                Re: Malloc Query luser- -droog <mijoryx@yahoo.com> - 2011-05-23 00:39 -0700
                Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-23 14:44 +0100
                Re: Malloc Query Seebs <usenet-nospam@seebs.net> - 2011-05-23 15:16 +0000
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-23 11:41 -0400
                Re: Malloc Query David Thompson <dave.thompson2@verizon.net> - 2011-06-01 16:33 -0400
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-19 18:34 -0400
                Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-20 02:36 +0100
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-20 12:26 -0400
                Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-20 23:32 +0100
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-20 21:17 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-21 14:30 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-21 11:13 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-22 08:50 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-21 20:03 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-22 13:23 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-22 10:01 -0400
                Re: Malloc Query "io_x" <a@b.c.invalid> - 2011-05-26 08:12 +0200
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-26 19:16 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-26 15:03 -0400
                Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-27 09:16 +1200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-26 17:55 -0400
                Re: Malloc Query "io_x" <a@b.c.invalid> - 2011-05-27 05:47 +0200
                Re: Malloc Query Uncle Steve <stevet810@gmail.com> - 2011-05-26 15:02 -0400
        Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 22:31 +0100
          Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-18 23:37 +0100
            Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-19 01:50 +0100
              Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 02:50 +0100
                Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-19 12:14 +0100
                Re: Malloc Query Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 15:10 +0100
                Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-19 15:48 +0100
      Re: Malloc Query cri@tiac.net (Richard Harter) - 2011-05-18 19:31 +0000
      Re: Malloc Query Ike Naar <ike@iceland.freeshell.org> - 2011-05-18 21:43 +0000
        Re: Malloc Query "BartC" <bc@freeuk.com> - 2011-05-18 22:58 +0100
  Re: Malloc Query Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-05-17 14:01 -0600
  Re: Malloc Query Columbus sailed the ocean China Blue <chine.bleu@yahoo.com> - 2011-05-17 13:21 -0700
  Re: Malloc Query BGB <cr88192@hotmail.com> - 2011-05-17 14:08 -0700
    Re: Malloc Query Michael Press <rubrum@pacbell.net> - 2011-05-17 19:49 -0700
  Re: Malloc Query Lauri Alanko <la@iki.fi> - 2011-05-18 00:50 +0000
  Re: Malloc Query Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-17 21:21 -0400
    Re: Malloc Query "io_x" <a@b.c.invalid> - 2011-05-18 19:31 +0200
    Re: Malloc Query Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-05-18 21:36 +0000
      Re: Malloc Query Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-18 21:26 -0400
    Re: Malloc Query Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-19 02:07 -0700
      Re: Malloc Query Ian Collins <ian-news@hotmail.com> - 2011-05-19 21:13 +1200
  Re: Malloc Query Nobody <nobody@nowhere.com> - 2011-05-18 07:08 +0100
  Re: Malloc Query David Resnick <lndresnick@gmail.com> - 2011-05-19 07:51 -0700
    Re: Malloc Query Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-05-19 09:12 -0600

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