[racket] Efficiency of tight loops in Racket

The construct 'thread' is as you describe. The construct 'future',
however, could easily (in a generic sense) be called a 'thread which
multi-threaded enabled cpu will run truly in parallel'. A place, too.
They have different restrictions. The words have precise technical
meanings in our language manuals, of course.

If you want to read more, try this:

  http://www.eecs.northwestern.edu/~robby/pubs/papers/oopsla2010-stdff.pdf

Robby

On Fri, Jan 14, 2011 at 5:35 PM, Harry Spier <harryspier at hotmail.com> wrote:
> Thanks.
>
> Perhaps some one could explain this aside in section 18.9 "Parallelism with
> futures"
>
> Other functions, such as thread, support the creation of reliably concurrent
> tasks. However, thread never run truly in parallel, even if the hardware and
> operating system support parallelism.
>
> Does that mean there is no way in Racket to create threads which a
> multi-threaded enabled cpu will run truly in parallel?
>
> Harry Spier
>
>
>
>> Date: Fri, 14 Jan 2011 15:30:22 -0600
>> Subject: Re: [racket] Efficiency of tight loops in Racket
>> From: robby at eecs.northwestern.edu
>> To: harryspier at hotmail.com
>> CC: matthias at ccs.neu.edu; eli at barzilay.org; users at racket-lang.org
>>
>> Please look at the future and the places library. These are still
>> relatively new parts of Racket, but we'd love to have your feedback.
>> Here's an overview, leading to futures:
>>
>> http://docs.racket-lang.org/guide/performance.html
>>
>> Robby
>>
>> On Fri, Jan 14, 2011 at 2:12 PM, Harry Spier <harryspier at hotmail.com>
>> wrote:
>> > Thanks Matthias.
>> >
>> > From whats been said perhaps the way to go is to make a C wrapper to the
>> > C
>> > interface to the latest version of ImageMagick and then go through the
>> > FFI
>> > to interface to Racket.
>> >
>> > Also someone mentioned the use of parallel processing.  It seems to me
>> > that
>> > an OCR application would be the ideal application for parallel
>> > processing.
>> > I.e. the analysis of one letter is completely independent of the
>> > analysis of
>> > another letter. So for example if you had a dual core processor with
>> > multithreading enabled you could analyse 4 letters concurrently etc. by
>> > setting up 4 threads.
>> >
>> >  Is it possible on a PC (windows or linux) in Racket or in fact in any
>> > language (even assembler) to check if it has a multi-core processors and
>> > how
>> > many cores and/or multi-threading enabled.  In which case you would know
>> > how
>> > many threads to set up to process letters in parallel?
>> >
>> >
>> > Thanks,
>> > Harry Spier
>> >
>> >
>> >
>> >> Subject: Re: [racket] Efficiency of tight loops in Racket
>> >> From: matthias at ccs.neu.edu
>> >> Date: Fri, 14 Jan 2011 12:12:28 -0500
>> >> CC: eli at barzilay.org; users at racket-lang.org;
>> >> robby at eecs.northwestern.edu
>> >> To: harryspier at hotmail.com
>> >>
>> >>
>> >> It's an experimental package under development for use with teaching
>> >> materials. It's not ready for anything really -- Matthias (I know, I
>> >> wrote
>> >> it)
>> >>
>> >>
>> >> On Jan 14, 2011, at 9:59 AM, Harry Spier wrote:
>> >>
>> >> >
>> >> > I thought I saw somewhere in the Racket documentation a few weeks ago
>> >> > that there is another graphics package in Racket that even has a
>> >> > function to
>> >> > create a binary matrix from a picture. But when I tried to find it
>> >> > yesterday
>> >> > I couldn't (I don't remember the name or where in the documentation I
>> >> > saw
>> >> > it).
>> >> >
>> >> > Does anyone know what package that could be?
>> >> >
>> >> > Thanks,
>> >> > Harry
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> > > From: eli at barzilay.org
>> >> > > Date: Fri, 14 Jan 2011 09:47:24 -0500
>> >> > > To: vasishtha.spier at gmail.com
>> >> > > CC: matthias at ccs.neu.edu; users at racket-lang.org;
>> >> > > robby at eecs.northwestern.edu; harryspier at hotmail.com
>> >> > > Subject: Re: [racket] Efficiency of tight loops in Racket
>> >> > >
>> >> > > 12 hours ago, Harry Spier wrote:
>> >> > > > 2) interface to ImageMagick (which I use to create my binary page
>> >> > > > representation)
>> >> > >
>> >> > > Note BTW that the ImageMagick interface that comes with racket was
>> >> > > made as an example for an interface, so it wasn't kept up to date
>> >> > > with
>> >> > > the current API. (I don't know what changed, but given that a
>> >> > > number
>> >> > > of years have passed, I'm guessing that updates are needed.)
>> >> > >
>> >> > > --
>> >> > > ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
>> >> > > http://barzilay.org/ Maze is Life!
>> >>
>> >
>