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Re: working with big numbers

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In article <pan.2012.05.17.17.43.13.654000@nowhere.com>,
Nobody  <nobody@nowhere.com> wrote:
>Also, heap allocation failure is usually easier to catch than stack
>allocation failure.

If you are writing code that is supposed to be reliable, it's much
better.  Check for no-mem, if so, clean up and report 'we're sorry, we
are unable to fulfill your request at this time'; or get SEGV...

well great now you screwed up the shared memory too

...

So this one time, some customer had a problem, they were running
thousands of threads and their requirements for stack were tight.

Then i found the problem:

    int smash_page(PAGE *page)
    {
	PAGE tmppage;

	...(page, tmppage)...

	memcpy(page, &tmppage, sizeof PAGE);
    }

Perfectly sensible, but when i switched it to use heap their problem
fixed itself.  I confirmed that the run-time was negligible.

For multi-thread, heap memory needs as much memory as is needed at one
time, while stack memory needs as much memory as all of them will need
at some time.

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working with big numbers ashu <ashishmourya21@gmail.com> - 2012-05-13 08:42 -0700
  Re: working with big numbers thomas.mertes@gmx.at - 2012-05-13 09:48 -0700
    Re: working with big numbers Ike Naar <ike@sverige.freeshell.org> - 2012-05-15 07:19 +0000
      Re: working with big numbers Nils M Holm <news2009@t3x.org> - 2012-05-15 07:56 +0000
        Re: working with big numbers Ike Naar <ike@sverige.freeshell.org> - 2012-05-15 14:11 +0000
  Re: working with big numbers thomas.mertes@gmx.at - 2012-05-13 10:00 -0700
  Re: working with big numbers Barry Schwarz <schwarzb@dqel.com> - 2012-05-14 15:53 -0700
  Re: working with big numbers bl0ckedusersoft@gmail.com - 2012-05-14 13:11 -0700
    Re: working with big numbers Noob <root@127.0.0.1> - 2012-05-15 11:37 +0200
      Re: working with big numbers Bl0ckeduser <bl0ckedusersoft@gmail.com> - 2012-05-15 10:11 -0400
        Re: working with big numbers nick_keighley_nospam@hotmail.com - 2012-05-17 02:42 -0700
          Re: working with big numbers Nobody <nobody@nowhere.com> - 2012-05-17 18:43 +0100
            Re: working with big numbers jgk@panix.com (Joe keane) - 2012-05-18 21:57 +0000
          Re: working with big numbers Bl0ckeduser <bl0ckedusersoft@gmail.com> - 2012-05-17 17:44 -0400
    Re: working with big numbers Peter Nilsson <airia@acay.com.au> - 2012-05-16 15:38 -0700
      Re: working with big numbers Bl0ckeduser <bl0ckedusersoft@gmail.com> - 2012-05-16 22:01 -0400
  Re: working with big numbers Paul <nospam@needed.com> - 2012-05-14 19:44 -0400
  Re: working with big numbers Robert Miles <robertmilesxyz@gmail.com> - 2012-05-14 18:16 -0700
  Re: working with big numbers Ike Naar <ike@sverige.freeshell.org> - 2012-05-15 06:50 +0000
  Re: working with big numbers Nils M Holm <news2009@t3x.org> - 2012-05-15 07:06 +0000
  Re: working with big numbers James Dow Allen <jdallen2000@yahoo.com> - 2012-05-15 02:13 -0700
    Re: working with big numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-15 11:07 +0100
      Re: working with big numbers Nils M Holm <news2009@t3x.org> - 2012-05-15 11:10 +0000
        Re: working with big numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-15 15:03 +0100
          Re: working with big numbers Bl0ckeduser <bl0ckedusersoft@gmail.com> - 2012-05-15 10:34 -0400
  Re: working with big numbers Edwin van den Oetelaar <newsgroups@oetelaar.com> - 2012-05-17 13:14 +0200
    Re: working with big numbers "BartC" <bc@freeuk.com> - 2012-05-17 12:34 +0100

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