Re: realloc() - frequency, conditions, or experiences about relocation?

From	Anton Shepelev <anton.txt@g{oogle}mail.com>
Newsgroups	comp.lang.c, sci.stat.math
Subject	Re: realloc() - frequency, conditions, or experiences about relocation?
Date	2024-06-19 15:20 +0300
Organization	A noiseless patient Spider
Message-ID	<20240619152000.2738defeceb1df7203151c64@g{oogle}mail.com> (permalink)
References	(2 earlier) <v4ovqf$j5hq$1@dont-email.me> <87zfrjvqp6.fsf@bsb.me.uk> <v4pb4v$lhgk$1@dont-email.me> <20240617180249.96dfaafa89392827aa162434@g{oogle}mail.com> <v4tuvf$1qto5$1@dont-email.me>

Cross-posted to 2 groups.

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Malcolm McLean writes that, given the log-normal distribution
of file sizes with known parameters,

> we can work out, given that a file is at least N
> characters, what is the prbablity that an allocation of
> any size will contain the whole file, and how many bytes,
> on average will be wasted.

This is why I thought statisticians might help him: Malcolm
wants to find the aposteriori distribution of the size of a
file, after it has been found to exceed N bytes.  Am I right
that if we take the remaining (N>20) part of the density
function and re-normalise it, we shall obtain the desired
distribution?

My proposition was as follows:

  1.  Find quantile q0 corresponding to the buffer size
      currently requested.

  2.  Calculate new quantile q1 = 1-(1-q0)/k, where k>1 is
      an adjustable parameter, and use its corresponding
      value as the new allocation size.

For example, assuming for simplicity a uniform [0,20]
distribution of file sizez and k=2, a sequence of allocation
may look like this:

                requested allocated
                 2        20-(20- 2)/2 = 11
                12        20-(20-12)/2 = 16
                18        20-(20-18)/2 = 19
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Re: realloc() - frequency, conditions, or experiences about relocation? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2024-06-17 18:02 +0300
  Re: realloc() - frequency, conditions, or experiences about relocation? "David Jones" <dajhawk18xx@@nowhere.com> - 2024-06-18 17:59 +0000
  Re: realloc() - frequency, conditions, or experiences about relocation? davidd02@tpg.com.au (David Duffy) - 2024-06-19 06:48 +0000
    Re: realloc() - frequency, conditions, or experiences about relocation? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-06-19 10:12 +0100
      Re: realloc() - frequency, conditions, or experiences about relocation? Ben Bacarisse <ben@bsb.me.uk> - 2024-06-19 16:36 +0100
        Re: realloc() - frequency, conditions, or experiences about relocation? David Brown <david.brown@hesbynett.no> - 2024-06-19 19:41 +0200
          Re: realloc() - frequency, conditions, or experiences about relocation? Ben Bacarisse <ben@bsb.me.uk> - 2024-06-19 22:24 +0100
      Re: realloc() - frequency, conditions, or experiences about relocation? Anton Shepelev <anton.txt@gmail.moc> - 2024-06-20 01:53 +0300
        Re: realloc() - frequency, conditions, or experiences about relocation? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2024-07-08 19:34 +0300
    Re: realloc() - frequency, conditions, or experiences about relocation? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2024-06-19 15:20 +0300
  Re: realloc() - frequency, conditions, or experiences about relocation? Rich Ulrich <rich.ulrich@comcast.net> - 2024-07-02 00:51 -0400
    Re: realloc() - frequency, conditions, or experiences about relocation? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-07-01 22:10 -0700
      Re: realloc() - frequency, conditions, or experiences about relocation? Rich Ulrich <rich.ulrich@comcast.net> - 2024-07-02 11:45 -0400
        Re: realloc() - frequency, conditions, or experiences about relocation? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2024-07-08 20:01 +0300
          Re: realloc() - frequency, conditions, or experiences about relocation? Rich Ulrich <rich.ulrich@comcast.net> - 2024-07-21 19:40 -0400
            Re: realloc() - frequency, conditions, or experiences about relocation? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2024-07-23 16:47 +0300
    Re: realloc() - frequency, conditions, or experiences about relocation? Paul <nospam@needed.invalid> - 2024-07-02 03:02 -0400
      Re: realloc() - frequency, conditions, or experiences about relocation? Rich Ulrich <rich.ulrich@comcast.net> - 2024-07-02 11:52 -0400
        Re: realloc() - frequency, conditions, or experiences about relocation? Rich Ulrich <rich.ulrich@comcast.net> - 2024-07-02 11:58 -0400
          Re: realloc() - frequency, conditions, or experiences about relocation? Paul <nospam@needed.invalid> - 2024-07-02 15:09 -0400
            Re: realloc() - frequency, conditions, or experiences about relocation? James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-07-02 16:54 -0400
            Re: realloc() - frequency, conditions, or experiences about relocation? James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-07-02 16:58 -0400

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