The following shows 100% cpu usage on both processors of my dual core machine running with Windows 7. I don't know why my earlier attemps, some time ago, did not work. I now see that the docs tell that futures are supported for Windows too. Thanks, Jos.
DrRacket, version 5.0.99.6--2011-01-18(c12d52f/a) [3m]. #lang racket (require racket/future) (processor-count) ; -> 2 (define f (future (lambda () (let loop () (loop))))) (let loop () (loop)) ; (touch f) > -----Original Message----- > From: users-boun...@racket-lang.org > [mailto:users-boun...@racket-lang.org] On Behalf Of Jos Koot > Sent: 18 January 2011 09:31 > To: 'Robby Findler' > Cc: users@racket-lang.org > Subject: Re: [racket] Efficiency of tight loops in Racket > > I have seen these pages before. There are many caveats and I > probably went into them. I'll try to do the mandelbrot > example in its various versions and compare their timings, > while observing CPU usage. > Jos > > > -----Original Message----- > > From: robby.find...@gmail.com > > [mailto:robby.find...@gmail.com] On Behalf Of Robby Findler > > Sent: 17 January 2011 21:56 > > To: Jos Koot > > Cc: Noel Welsh; users@racket-lang.org > > Subject: Re: [racket] Efficiency of tight loops in Racket > > > > If you have not seen this yet, this is where you want to start: > > > > http://docs.racket-lang.org/guide/performance.html#%28part._ef > fective-futures%29 > > > > Robby > > > > On Mon, Jan 17, 2011 at 2:40 PM, Jos Koot <jos.k...@telefonica.net> > > wrote: > > > I trieed some examples of my own. But I shall try the > > examples of the > > > docs ASAP. > > > More tomorrow, for now it's my bedtime. > > > Jos > > > > > > > > > > > > > > >> -----Original Message----- > > >> From: robby.find...@gmail.com > > >> [mailto:robby.find...@gmail.com] On Behalf Of Robby Findler > > >> Sent: 17 January 2011 20:43 > > >> To: Jos Koot > > >> Cc: Noel Welsh; users@racket-lang.org > > >> Subject: Re: [racket] Efficiency of tight loops in Racket > > >> > > >> With futures you have to be careful; it is easy to write > code that > > >> doesn't end up actually being parallel. Did you try the > > examples from > > >> the docs? > > >> > > >> Robby > > >> > > >> On Mon, Jan 17, 2011 at 1:27 PM, Jos Koot > > <jos.k...@telefonica.net> > > >> wrote: > > >> > I did try futures, but did not observe two processors > being used > > >> > simultaneously. > > >> > Jos > > >> > > > >> >> -----Original Message----- > > >> >> From: robby.find...@gmail.com > > >> >> [mailto:robby.find...@gmail.com] On Behalf Of Robby Findler > > >> >> Sent: 17 January 2011 20:22 > > >> >> To: Jos Koot > > >> >> Cc: Noel Welsh; users@racket-lang.org > > >> >> Subject: Re: [racket] Efficiency of tight loops in Racket > > >> >> > > >> >> Oh, yes. DrRacket does not try to use two processors > > for anything > > >> >> (unless your program uses futures or places, of course). > > >> >> > > >> >> Robby > > >> >> > > >> >> On Mon, Jan 17, 2011 at 10:25 AM, Jos Koot > > >> <jos.k...@telefonica.net> > > >> >> wrote: > > >> >> > Thanks for your reply. > > >> >> > What I am observing is that when running DrScheme > > >> without any other > > >> >> > apps running, only one processor is used at a time, > > >> >> although control > > >> >> > often swichtes bnetween the two processors. I also > > observe that > > >> >> > windows 7 aborts DrScheme when more than 2Gbyte of > > >> memory is being > > >> >> > used. I have set the memory limit of DrScheme to > > infite and for > > >> >> > windows to about 5 Gbyte. Under windows xp virtual memory > > >> >> did function > > >> >> > well, but that was with 1 Gbyte of memory and > > trashing made it > > >> >> > impossible to go up to 2 Gbyte. Now I have two cores of 2 > > >> >> Gbyte, but can't put my machine to thrash on page swapping. > > >> >> > Jos > > >> >> > > > >> >> >> -----Original Message----- > > >> >> >> From: robby.find...@gmail.com > > >> >> >> [mailto:robby.find...@gmail.com] On Behalf Of Robby Findler > > >> >> >> Sent: 17 January 2011 16:14 > > >> >> >> To: Noel Welsh > > >> >> >> Cc: Jos Koot; users@racket-lang.org > > >> >> >> Subject: Re: [racket] Efficiency of tight loops in Racket > > >> >> >> > > >> >> >> I think the real reason is actually much sadder: no one on > > >> >> the core > > >> >> >> team regularly uses windows. Well, until about a month > > >> ago, when I > > >> >> >> started using windows for my development tasks so > > >> >> hopefully that'll > > >> >> >> change. > > >> >> >> > > >> >> >> But I'm not sure what Jos is observing and I was > > >> expecting a reply > > >> >> >> from Kevin or Matthew on this -- places are still pretty > > >> >> >> experimental. > > >> >> >> > > >> >> >> Robby > > >> >> >> > > >> >> >> On Mon, Jan 17, 2011 at 8:58 AM, Noel Welsh > > >> <noelwe...@gmail.com> > > >> >> >> wrote: > > >> >> >> > I've seen lots of recent commits dealing w/ Windows 7 > > >> / 64-bit > > >> >> >> > support, so I expect it is simply time. Windows is not > > >> >> as developer > > >> >> >> > friendly as Unix so likely to receive new > features last (as > > >> >> >> a guess). > > >> >> >> > > > >> >> >> > N. > > >> >> >> > > > >> >> >> > On Sat, Jan 15, 2011 at 5:22 PM, Jos Koot > > >> >> >> <jos.k...@telefonica.net> wrote: > > >> >> >> >> Is there a specific reason why there is no parallel > > >> >> >> support for place > > >> >> >> >> on a dual core processor with Windows 7. > > >> >> >> >> Thanks, Jos > > >> >> >> > _________________________________________________ > > >> >> >> > For list-related administrative tasks: > > >> >> >> > http://lists.racket-lang.org/listinfo/users > > >> >> >> > > > >> >> > > > >> >> > > > >> > > > >> > > > > > > > > > _________________________________________________ > For list-related administrative tasks: > http://lists.racket-lang.org/listinfo/users _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
