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

From	Malcolm McLean <malcolm.arthur.mclean@gmail.com>
Newsgroups	comp.lang.c, sci.stat.math
Subject	Re: realloc() - frequency, conditions, or experiences about relocation?
Date	2024-06-19 10:12 +0100
Organization	A noiseless patient Spider
Message-ID	<v4u7dm$1t2pu$1@dont-email.me> (permalink)
References	(2 earlier) <v4ovqf$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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On 19/06/2024 07:48, David Duffy wrote:
> In sci.stat.math Anton Shepelev <anton.txt@g{oogle}mail.com> wrote:
>> [cross-posted to: ci.stat.math]
>>
>> Malcolm McLean:
>>
>>> We have a continuously growing buffer, and we want the
>>> best strategy for reallocations as the stream of
>>> characters comes at us. So, given we now how many
>>> characters have arrived, can we predict how many will
>>> arrive,
>>
>> Do you mean in the next bunch, or in total (till the end of
>> the buffer's lifetime)?
>>
> Isn't this a halting problem?  Aren't the more important data:
> how much memory the user is allowed to allocate, the properties of
> the current system's memory allocation algorithm, when your stream
> will have to go to disc or other slow large volume storage, how
> the stream can be compressed on the fly (the latter might well give
> strong predictions for future storage requirements based on what
> has been read to date).
> 
> 
No. We have to have some knowledge. And what we probaby know is that the 
input is a file stored on someone's personal computer. And someone has 
published on the statistical distribution of such files And they have a 
log-normal distribution with a mean and a median which he gives. So with 
that informaton, 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.

Statistical analysis can't tell us what a allocation wil cost versus the 
cost of hoggng memory we don't need, however. It can;t tell us what to 
do. Just put us in the picture.
-- 
Check out my hobby project.
http://malcolmmclean.github.io/babyxrc

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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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