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Re: Reclaiming Allocated Memory

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Doug Hoffman <glidedog@gmail.com> writes:
>On 12/6/13 11:30 AM, Bernd Paysan wrote:
>> In a simple allocater like the one for region based memory, you can shrink
>> all objects in place, and to grow them, you need to copy them to a new
>> location, unless they are the last allocated object (in which case growing
>> them is almost for free).
>
>That last point is a good one.  Thanks.

Yes, if you RESIZE the last allocated thing, and the result fits in
the current block, then it's cheap.  But with my current
implementation, every other RESIZE, even if it shrinks, is expensive:
I don't know the old size of the resized thing, so I always allocate
new memory, and the amount of memory I copy there is usually bigger
(possibly much bigger) than the old size.

I have been thinking about a different implementation for resized
stuff, but if RESIZE is not going to be used much in combination with
region-based memory allocation, the benefit is not worth the effort.
That kind of implementation would put each resized thing in its own
block, plus some meta-data.

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: http://www.forth200x.org/forth200x.html
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Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-11-25 07:41 -0500
  Re: Reclaiming Allocated Memory Paul Rubin <no.email@nospam.invalid> - 2013-11-25 07:04 -0800
    Re: Reclaiming Allocated Memory albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-11-25 16:16 +0000
      Re: Reclaiming Allocated Memory Paul Rubin <no.email@nospam.invalid> - 2013-11-25 09:03 -0800
        Re: Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-11-26 06:30 -0500
          Re: Reclaiming Allocated Memory AKK <akk@nospam.org> - 2013-11-26 13:07 +0100
    Re: Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-11-26 05:11 -0500
  Re: Reclaiming Allocated Memory anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-12-04 16:46 +0000
    Re: Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-12-05 06:43 -0500
      Re: Reclaiming Allocated Memory Paul Rubin <no.email@nospam.invalid> - 2013-12-05 06:30 -0800
        Re: Reclaiming Allocated Memory albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-12-05 14:37 +0000
          Re: Reclaiming Allocated Memory Paul Rubin <no.email@nospam.invalid> - 2013-12-05 07:21 -0800
        Re: Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-12-06 04:57 -0500
          Re: Reclaiming Allocated Memory Paul Rubin <no.email@nospam.invalid> - 2013-12-06 07:38 -0800
            Re: Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-12-07 06:14 -0500
      Re: Reclaiming Allocated Memory anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-12-05 18:14 +0000
        Re: Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-12-06 04:58 -0500
          Re: Reclaiming Allocated Memory Bernd Paysan <bernd.paysan@gmx.de> - 2013-12-06 17:30 +0100
            Re: Reclaiming Allocated Memory Doug Hoffman <glidedog@gmail.com> - 2013-12-07 05:59 -0500
              Re: Reclaiming Allocated Memory anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-12-07 11:57 +0000
                Re: Reclaiming Allocated Memory albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-12-07 17:48 +0000
                Re: Reclaiming Allocated Memory Bernd Paysan <bernd.paysan@gmx.de> - 2013-12-07 19:15 +0100
                Re: Reclaiming Allocated Memory anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-12-09 13:45 +0000
          Re: Reclaiming Allocated Memory anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-12-06 17:42 +0000

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