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Re: Competing criteria

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Roberto Waltman <usenet@rwaltman.com> writes:
> Seebs  wrote:
> >  the canonical
> >solution to "not heap allocation" is to define a reasonable maximum count
> >of simultaneous objects, statically allocate them, and then basically
> >write your own mini-allocator that keeps track of which ones you're using.
> >This, you will note, is probably stupid.
> 
> Far from being stupid, that is the only way you can guarantee that
> memory allocation will not fail due to memory fragmentation, in
> systems with limited resources, no virtual memory and that must run
> 24/7.

False, and likely to fail in most embedded scenarios I've worked on.
Likely to fail, as if you have 100 units of RAM, and may need up to 20
of size 5, or 5 of size 20, but not simultaniously, then you must use
dynamic allocation.

And false, because if you never hand out pointers, but handles, then
you can use dynamic memory allocation and compact your heap either in
the background or on demand.

Phil
-- 
Unix is simple. It just takes a genius to understand its simplicity
-- Dennis Ritchie (1941-2011), Unix Co-Creator

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Competing criteria nroberts <roberts.noah@gmail.com> - 2011-10-21 14:49 -0700
  Re: Competing criteria Seebs <usenet-nospam@seebs.net> - 2011-10-21 22:16 +0000
    Re: Competing criteria Roberto Waltman <usenet@rwaltman.com> - 2011-10-22 14:06 -0400
      Re: Competing criteria Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-22 16:47 -0400
        Re: Competing criteria Ark <akhasin@macroexpressions.com> - 2011-10-22 17:33 -0400
          Re: Competing criteria Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-22 18:20 -0400
            Re: Competing criteria Ark <akhasin@macroexpressions.com> - 2011-10-22 21:29 -0400
            Re: Competing criteria "io_x" <a@b.c.invalid> - 2011-10-23 10:32 +0200
              Re: Competing criteria "Joachim Schmitz" <nospam.jojo@schmitz-digital.de> - 2011-10-23 11:06 +0200
                Re: Competing criteria Willem <willem@toad.stack.nl> - 2011-10-23 09:09 +0000
                Re: Competing criteria "io_x" <a@b.c.invalid> - 2011-10-23 12:04 +0200
                Re: Competing criteria "io_x" <a@b.c.invalid> - 2011-10-27 08:44 +0200
                Re: Competing criteria Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-10-23 05:01 -0700
            Re: Competing criteria Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-10-23 08:29 -0400
              Re: Competing criteria Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-23 09:15 -0400
                Re: Competing criteria Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-10-23 06:24 -0700
                Re: Competing criteria Markus Wichmann <nullplan@gmx.net> - 2011-10-24 22:39 +0200
                Re: Competing criteria Keith Thompson <kst-u@mib.org> - 2011-10-24 17:10 -0700
                Re: Competing criteria Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-10-25 13:09 +0300
                Re: Competing criteria Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-10-26 00:23 -0700
      Re: Competing criteria Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-10-23 00:02 +0300
      Re: Competing criteria Seebs <usenet-nospam@seebs.net> - 2011-10-24 20:10 +0000
        Re: Competing criteria Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-24 19:36 -0400
        Re: Competing criteria nroberts <roberts.noah@gmail.com> - 2011-10-25 10:07 -0700
          Re: Competing criteria Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-25 16:51 -0400
  Re: Competing criteria John Gordon <gordon@panix.com> - 2011-10-21 22:37 +0000
  Re: Competing criteria Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-21 20:42 -0400

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