Re: High level C

From	Les Cargill <lcargill99@comcast.com>
Newsgroups	comp.lang.c
Subject	Re: High level C
Date	2016-08-01 00:54 -0500
Organization	A noiseless patient Spider
Message-ID	<nnmntn$4ps$1@dont-email.me> (permalink)
References	(7 earlier) <kfnvazlnb8l.fsf@x-alumni2.alumni.caltech.edu> <20160731164221.2f1d338d@maxa-pc> <kfna8gxmve1.fsf@x-alumni2.alumni.caltech.edu> <nnlsql$7td$1@dont-email.me> <kfnfuqpl53h.fsf@x-alumni2.alumni.caltech.edu>

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Tim Rentsch wrote:
> Les Cargill <lcargill99@comcast.com> writes:
>
>> Tim Rentsch wrote:
>>> Melzzzzz <mel@zzzzz.com> writes:
>>>
>>>> On Sun, 31 Jul 2016 07:16:58 -0700
>>>> Tim Rentsch <txr@alumni.caltech.edu> wrote:
>>>>
>>>>> There is a common belief in some circles that GC incurs a
>>>>> substantial performance penalty relative to manual coding of
>>>>> free(), etc.  Experience with actual systems does not bear this
>>>>> out.  Indeed, the experience in some large code bases has been
>>>>> that switching to GC actually improves performance.
>>>>
>>>> Care to show links?
>>>
>>> Unfortunately I don't know any.  The only specific examples I
>>> know of are proprietary.  I am not aware of any where the
>>> results are publically available.
>>>
>>>> I find hardly to believe that deallocation increase
>>>> performance...
>>>> Stopping program to perform memory scan and trashing memory in process
>>>> is faster?  how so?
>>>
>>> I think it's pretty easy to understand.  If you do manual
>>> deallocation, bookkeeping needs to be done to keep track of what
>>> is referenced to know when something can be deallocated.
>>
>> No, you simply have to have an explicit context for the lifetime of
>> objects.  I personally have never witnessed where this was all that
>> onerous.  Most things we do can be chunked into "frames" like that.
>
> Certainly that can be done in some cases.  I believe there
> are also cases where it cannot be done, or at least cannot
> be done without a fair amount of difficulty.  I didn't
> mean to say that getting a performance improvement is
> typical, only that it does sometimes occur in real cases.
>

I'm  not sure what you're after here. Most 'C' programs I've used
may use dynamic ( or, more probably semi-dynamic) allocation behind
the scenes but applications I've dealt with largely tended to
accumulate a set of buffers and working storage, and after a short
while, became memory-stable.

For the curious, this does indeed include things that have significant
levels of dynamically configured objects that get created and
destroyed. You can often see the same sort of approach taken in the 
Linux kernel - configuration options for the maximum number of object
<x> are part of the kernel build. This creates arrays that are then
dynamically used.

This is just a very 'C' thing to do.

>>>   A
>>> well-written garbage collector can do a better job of doing that
>>> bookkeeping efficiently.  That isn't to say that the manual
>>> bookkeeping code has to run slower than what the GC does, only
>>> that it did in the particular cases.
>>
>> To me, trying to pretend that object lifetime can be automated seems
>> questionable at best.
>
> I have found that how I think a system will behave and how it
> actually behaves are sometimes quite different.  That is why
> whenever possible I prefer to give results from actual
> experiments rather than thought experiments.
>

Sure.

>> I'm not saying interpreters which use GC are bad, just that this solves
>> a rather small problem
>
> Certainly there are some applications that do not (or would not)
> benefit from using automatic storage reclamation (eg, garbage
> collection).  But I think there are some that do (or would),
> and it would be nice to have choice for working in those areas.
>

-- 
Les Cargill

Thread

High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-15 23:36 +0200
  Re: High level C supercat@casperkitty.com - 2016-07-15 15:17 -0700
    Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-16 09:09 +0200
      Re: High level C supercat@casperkitty.com - 2016-07-17 20:02 -0700
  Re: High level C Keith Thompson <kst-u@mib.org> - 2016-07-15 15:17 -0700
    Re: High level C fir <profesor.fir@gmail.com> - 2016-07-31 23:55 -0700
  Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-15 23:27 +0100
    Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-16 09:13 +0200
      Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-16 02:07 -0700
        Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-16 11:07 +0100
          Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-16 03:29 -0700
            Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-16 13:40 +0100
            Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-17 11:57 +0530
          Re: High level C BartC <bc@freeuk.com> - 2016-07-16 11:30 +0100
            Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-16 03:43 -0700
              Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-16 13:53 +0100
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-16 07:49 -0700
                Re: High level C Jean-Marc Bourguet <jm@bourguet.org> - 2016-07-16 17:08 +0200
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-16 09:09 -0700
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-16 16:26 +0100
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-16 18:05 +0200
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-16 20:15 +0100
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-16 23:44 +0200
                Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-07-23 19:39 +0000
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-23 22:58 +0200
                Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-07-27 14:52 +0000
                Re: High level C Richard Heathfield <rjh@cpax.org.uk> - 2016-07-27 16:29 +0100
                Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-07-23 19:38 +0000
              Re: High level C BartC <bc@freeuk.com> - 2016-07-16 14:17 +0100
            Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-16 13:46 +0100
            Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-17 12:05 +0530
              Re: High level C BartC <bc@freeuk.com> - 2016-07-17 11:03 +0100
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-17 03:39 -0700
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-17 18:20 +0530
                Re: High level C BartC <bc@freeuk.com> - 2016-07-17 14:00 +0100
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-17 23:13 +0530
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-17 20:14 +0200
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-17 20:14 +0100
                Re: High level C BartC <bc@freeuk.com> - 2016-07-17 20:45 +0100
                Re: High level C Gareth Owen <gwowen@gmail.com> - 2016-07-17 21:00 +0100
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-18 09:48 +0530
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-18 00:55 -0700
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-18 22:25 +0530
                Re: High level C BartC <bc@freeuk.com> - 2016-07-18 11:40 +0100
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-18 05:05 -0700
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-18 22:59 +0530
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-18 22:50 +0530
                Re: High level C BartC <bc@freeuk.com> - 2016-07-18 19:07 +0100
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-19 11:53 +0530
                Re: High level C BartC <bc@freeuk.com> - 2016-07-19 11:15 +0100
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-19 14:00 +0100
                Re: High level C BartC <bc@freeuk.com> - 2016-07-19 15:01 +0100
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-19 15:26 +0100
                Re: High level C BartC <bc@freeuk.com> - 2016-07-19 15:57 +0100
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-19 17:13 +0100
                Re: High level C BartC <bc@freeuk.com> - 2016-07-19 18:14 +0100
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-19 19:20 +0100
                Re: High level C BartC <bc@freeuk.com> - 2016-07-19 19:46 +0100
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-20 02:44 +0100
                Re: High level C BartC <bc@freeuk.com> - 2016-07-20 10:59 +0100
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-20 03:07 -0700
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-21 01:44 +0100
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-21 18:58 +0530
                Re: High level C BartC <bc@freeuk.com> - 2016-07-21 17:20 +0100
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-21 20:52 +0100
                Re: High level C BartC <bc@freeuk.com> - 2016-07-21 21:14 +0100
                Re: High level C Keith Thompson <kst-u@mib.org> - 2016-07-21 13:23 -0700
                Re: High level C BartC <bc@freeuk.com> - 2016-07-21 21:50 +0100
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-22 12:52 +0200
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-22 04:03 -0700
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-22 23:56 +0530
                Re: High level C BartC <bc@freeuk.com> - 2016-07-22 20:09 +0100
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-22 23:49 +0530
                Re: High level C BartC <bc@freeuk.com> - 2016-07-22 20:37 +0100
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-19 19:16 +0200
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-19 19:17 +0100
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-19 21:07 +0200
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-20 02:36 +0100
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-19 07:27 -0700
                Re: High level C BartC <bc@freeuk.com> - 2016-07-19 16:27 +0100
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-07-19 08:43 -0700
                Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-19 19:14 +0100
                Re: High level C Jean-Marc Bourguet <jm@bourguet.org> - 2016-07-18 10:08 +0200
                Re: High level C Udyant Wig <udyant.wig@gmail.com> - 2016-07-18 23:04 +0530
      Re: High level C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-16 10:18 +0100
    Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-07-23 19:26 +0000
      Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-25 09:21 -0700
        Re: High level C luser droog <luser.droog@gmail.com> - 2016-07-25 10:19 -0700
          Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-28 10:31 -0700
            Re: High level C luser droog <luser.droog@gmail.com> - 2016-07-28 21:13 -0700
              Re: High level C supercat@casperkitty.com - 2016-07-29 09:05 -0700
                Re: High level C Keith Thompson <kst-u@mib.org> - 2016-07-29 09:30 -0700
                Re: High level C supercat@casperkitty.com - 2016-07-29 10:08 -0700
                Re: High level C Ike Naar <ike@iceland.freeshell.org> - 2016-07-29 17:57 +0000
                Re: High level C supercat@casperkitty.com - 2016-07-29 11:50 -0700
              Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-31 07:16 -0700
                Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-07-31 14:34 +0000
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-31 14:55 -0700
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-08-01 03:10 -0700
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-01 07:40 -0700
                Re: High level C Gareth Owen <gwowen@gmail.com> - 2016-08-01 19:43 +0100
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-01 10:21 -0500
                Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-08-03 13:14 +0000
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-05 08:40 -0700
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-08-05 09:28 -0700
                Re: High level C fir <profesor.fir@gmail.com> - 2016-08-05 09:55 -0700
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-05 15:51 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-05 18:43 +0200
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-05 15:43 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-06 00:52 +0200
                Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-08-10 12:42 +0000
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-11 12:24 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-07-31 16:42 +0200
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-31 12:59 -0700
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-07-31 17:12 -0500
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-31 17:12 -0700
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-01 00:54 -0500
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-01 08:08 -0700
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-01 12:58 -0500
                Re: High level C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-08-01 12:25 -0700
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-03 08:44 -0700
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-03 11:56 -0500
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-08-03 19:29 +0200
                Re: High level C "James R. Kuyper" <jameskuyper@verizon.net> - 2016-08-03 13:45 -0400
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-03 13:23 -0500
                Re: High level C BartC <bc@freeuk.com> - 2016-08-03 19:27 +0100
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-08-03 21:04 +0200
                Re: High level C Gareth Owen <gwowen@gmail.com> - 2016-08-03 20:08 +0100
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-03 16:09 -0500
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-03 16:06 -0500
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-08-03 23:36 +0200
                Re: High level C Les Cargill <lcargill99@comcast.com> - 2016-08-03 19:44 -0500
                Re: High level C supercat@casperkitty.com - 2016-08-03 15:03 -0700
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-04 19:17 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-05 05:48 +0200
                Re: High level C Keith Thompson <kst-u@mib.org> - 2016-08-05 08:24 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-05 18:30 +0200
                Re: High level C Keith Thompson <kst-u@mib.org> - 2016-08-05 10:34 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-05 20:50 +0200
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-05 15:39 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-06 00:50 +0200
                Re: High level C Keith Thompson <kst-u@mib.org> - 2016-08-05 17:08 -0700
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-06 02:23 +0200
                Re: High level C raltbos@xs4all.nl (Richard Bos) - 2016-08-06 10:03 +0000
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-06 12:13 +0200
                Re: High level C "James R. Kuyper" <jameskuyper@verizon.net> - 2016-08-06 11:10 -0400
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-06 17:40 +0200
                Re: High level C "James R. Kuyper" <jameskuyper@verizon.net> - 2016-08-06 11:56 -0400
                Re: High level C Melzzzzz <mel@zzzzz.com> - 2016-08-06 17:51 +0200
                Re: High level C supercat@casperkitty.com - 2016-08-08 09:12 -0700
                Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-31 22:07 +0200
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-07-31 15:05 -0700
                Re: High level C Ian Collins <ian-news@hotmail.com> - 2016-08-03 11:22 +1200
                Re: High level C Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-03 08:50 -0700
  Re: High level C BartC <bc@freeuk.com> - 2016-07-16 01:12 +0100
    Re: High level C Jerry Stuckle <jstucklex@attglobal.net> - 2016-07-15 20:16 -0400
    Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-16 09:17 +0200
  Re: High level C Siri Cruise <chine.bleu@yahoo.com> - 2016-07-16 08:20 -0700
    Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-16 17:24 +0200
      Re: High level C Siri Cruise <chine.bleu@yahoo.com> - 2016-07-16 09:24 -0700
  Re: High level C carlglassberg@gmail.com - 2016-07-17 14:15 -0700
  Re: High level C carlglassberg@gmail.com - 2016-07-17 14:22 -0700
    Re: High level C jacobnavia <jacob@jacob.remcomp.fr> - 2016-07-17 23:58 +0200
  Re: High level C fir <profesor.fir@gmail.com> - 2016-08-02 13:20 -0700

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