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Re: Windows8

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Doug Hoffman <glidedog@gmail.com> writes:
> A Forth GC implementation must have a memory and speed hit of its
> own. You're not likely to convince me to use GC because the problems I
> solve don't require it.

The only Forth GC that I know of is Anton's, which is a Boehm-style
conservative collector that scans the entire heap for anything that
might be a pointer, so its speed hit per collection is O(N) in the total
size of the strings.  Its space hit is small, maybe a bit or a cell in
each allocated object regardless of object size (not sure).  Your
copying approach is potentially much worse, like O(N*K) where K is the
number of copies made, and K could potentially itself be O(N), making
the whole thing O(N**2); and it is both a speed hit and a space hit of
that magnitude.  Whether the speed hit is worse depends of course on
collection frequency.

A more advanced GC usually doesn't scan the heap, but instead just
traces the pointers and copies the live data, so it's basically O(M) in
the live data size at each collection, where M is often much smaller
than N.  With this type of GC, allocation is similar to ALLOT (i.e. it
just bumps a pointer) and freeing most objects takes zero time (since
the GC doesn't touch dead objects).  GC is often faster than traditional
allocate/free for that reason.

> Perhaps others who have used Forth and GC could comment on what GC
> code they use and how that has worked out for them.  I've read
> negative comments about that.

I'd be interested in hearing experiences too.  I think GC is not really
a perfect fit for Forth, but it does exist and apparently gets used
sometimes.  I think for the sorts of problems that benefit a lot from
relying heavily on GC, Forth itself may not be that good a fit.  Forth
with GC is sort of an in-between area and I was surprised to find out
about it.

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Windows8 visualforth@rocketmail.com - 2012-11-02 08:41 -0700
  Re: Windows8 Brad Eckert <hwfwguy@gmail.com> - 2012-11-02 11:12 -0700
  Re: Windows8 visualforth@rocketmail.com - 2012-11-06 09:05 -0800
    Re: Windows8 Jason Damisch <jasondamisch@yahoo.com> - 2012-11-12 07:10 -0800
      Re: Windows8 stephenXXX@mpeforth.com (Stephen Pelc) - 2012-11-12 17:27 +0000
    Re: Windows8 visualforth@rocketmail.com - 2012-11-21 17:48 -0800
  Re: Windows8 visualforth@rocketmail.com - 2012-11-07 20:44 -0800
  Re: Windows8 Jason Damisch <jasondamisch@yahoo.com> - 2012-11-12 07:15 -0800
    Re: Windows8 Brad Eckert <hwfwguy@gmail.com> - 2012-11-12 07:59 -0800
    Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-12 07:55 -1000
      Re: Windows8 "Ed" <invalid@nospam.com> - 2012-11-14 20:04 +1100
        Re: Windows8 anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-14 17:01 +0000
          Re: Windows8 "Ed" <invalid@nospam.com> - 2012-11-18 11:14 +1100
            Re: Windows8 anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-19 14:25 +0000
              Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-19 08:09 -1000
                Re: Windows8 anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-20 09:55 +0000
                Re: Windows8 mhx@iae.nl (Marcel Hendrix) - 2012-11-25 10:56 +0200
                Re: Windows8 Bernd Paysan <bernd.paysan@gmx.de> - 2012-11-25 16:46 +0100
            Re: Windows8 Doug Hoffman <glidedog@gmail.com> - 2012-11-19 16:21 -0500
              Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-19 13:46 -0800
                Re: Windows8 Doug Hoffman <glidedog@gmail.com> - 2012-11-19 17:05 -0500
                Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-19 12:14 -1000
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-19 14:30 -0800
                Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-19 12:53 -1000
                Re: Windows8 Doug Hoffman <glidedog@gmail.com> - 2012-11-19 17:44 -0500
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-19 14:52 -0800
                GC (was Re: Windows8) Doug Hoffman <glidedog@gmail.com> - 2012-11-26 11:44 -0500
                Re: GC Paul Rubin <no.email@nospam.invalid> - 2012-11-26 11:44 -0800
                Re: GC Doug Hoffman <glidedog@gmail.com> - 2012-11-28 06:35 -0500
                Re: GC Paul Rubin <no.email@nospam.invalid> - 2012-11-29 11:58 -0800
                Re: GC albert@spenarnc.xs4all.nl (Albert van der Horst) - 2012-11-30 01:46 +0000
                Re: GC Paul Rubin <no.email@nospam.invalid> - 2012-11-29 21:14 -0800
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-19 14:42 -0800
                Re: Windows8 Doug Hoffman <glidedog@gmail.com> - 2012-11-19 17:56 -0500
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-19 15:14 -0800
                Re: Windows8 Doug Hoffman <glidedog@gmail.com> - 2012-11-19 18:45 -0500
                Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-19 14:18 -1000
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-19 16:18 -0800
                Re: Windows8 Doug Hoffman <glidedog@gmail.com> - 2012-11-19 19:01 -0500
                Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-19 12:58 -1000
                Re: Windows8 Bernd Paysan <bernd.paysan@gmx.de> - 2012-11-20 02:23 +0100
                Re: Windows8 anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-20 10:48 +0000
                Re: Windows8 Alex McDonald <blog@rivadpm.com> - 2012-11-20 07:56 -0800
                Re: Windows8 anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-21 15:03 +0000
                Re: Windows8 Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-11-23 05:58 -0800
                Re: Windows8 Mark Wills <forthfreak@gmail.com> - 2012-11-20 02:13 -0800
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-20 08:57 -0800
                Re: Windows8 "David N. Williams" <williams@umich.edu> - 2012-11-20 16:56 -0500
                Re: Windows8 mhx@iae.nl (Marcel Hendrix) - 2012-11-25 11:20 +0200
    Re: Windows8 rickman <gnuarm@gmail.com> - 2012-11-14 16:36 -0500
      Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-14 12:12 -1000
        Re: Windows8 rickman <gnuarm@gmail.com> - 2012-11-14 17:46 -0500
          Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-14 13:12 -1000
            Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-14 18:12 -0800
            Re: Windows8 rickman <gnuarm@gmail.com> - 2012-11-15 13:55 -0500
              Re: Windows8 RR <freedomspyder@gmail.com> - 2012-11-15 16:03 -0800
                Re: Windows8 rickman <gnuarm@gmail.com> - 2012-11-15 21:54 -0500
                Re: Windows8 RR <freedomspyder@gmail.com> - 2012-11-15 19:26 -0800
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-15 19:27 -0800
                Re: Windows8 Bernd Paysan <bernd.paysan@gmx.de> - 2012-11-16 17:45 +0100
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-16 09:10 -0800
                Re: Windows8 Bernd Paysan <bernd.paysan@gmx.de> - 2012-11-16 22:34 +0100
                Re: Windows8 Andy Valencia <vandys@vsta.org> - 2012-11-16 18:06 +0000
                Re: Windows8 Paul Rubin <no.email@nospam.invalid> - 2012-11-16 11:09 -0800
                Re: Windows8 Spam@ControlQ.com - 2012-11-16 15:18 -0500
        Re: Windows8 visualforth@rocketmail.com - 2012-11-15 00:19 -0800
          Re: Windows8 "Elizabeth D. Rather" <erather@forth.com> - 2012-11-14 22:55 -1000
          Re: Windows8 albert@spenarnc.xs4all.nl (Albert van der Horst) - 2012-11-15 12:20 +0000
            Re: Windows8 visualforth@rocketmail.com - 2012-11-15 08:32 -0800
            Re: Windows8 kenney@cix.compulink.co.uk - 2012-11-16 04:51 -0600
              Re: Windows8 stephenXXX@mpeforth.com (Stephen Pelc) - 2012-11-16 13:46 +0000
              Re: Windows8 visualforth@rocketmail.com - 2012-11-16 08:12 -0800
  Re: Windows8 the_gavino_himself <visphatesjava@gmail.com> - 2012-11-29 00:16 -0800

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