What you describe seems more like a bug in partitions than a documentation bug. Do you have a small example that provoke a segfault?
/Jens Axel 2014-07-17 12:41 GMT+02:00 Jos Koot <jos.k...@gmail.com>: > The documentation of partitions has not yet been updated, as far as I can > see in version 6.0.1.13--2014-07-08(7735dd0/a) [3m]. I don't want to hurry > up things (there may be other priorities) but when the docs will be updated, > I think they should include a warning against calling function partitions > from two concurrently running futures or threads. Reason is the non atomic > memoization. (let alone calling set-partitions-cache in one process while > another one is consulting/updating the cache) > > Calling partitions from two concurrent futures gives me a segfault. Not a > surprise. > Up to now calling from two concurrent threads gives me correct results, but > slows down vvveeerrryyy much. > I assume concurrent threads can lead to the same problems as concurrent > futures, though. > If I understand places correctly, calling from concurrent places should go > well. Do I understand correctly? > > Jos > >> -----Original Message----- >> From: Vincent St-Amour [mailto:stamo...@ccs.neu.edu] >> Sent: domingo, 29 de junio de 2014 22:52 >> To: Eric Dobson >> Cc: Jos Koot; Matthew Flatt; Jens Axel Søgaard; Racket Users List >> Subject: Re: [racket] FW: q about code for partitions >> >> Ah, that explains it. Thanks! >> >> Vincent >> >> >> At Sun, 29 Jun 2014 12:32:48 -0700, >> Eric Dobson wrote: >> > >> > Vincent: exact-zero? is defined through 'make-predicate' which uses >> > contract machinery to generate the function. I filed a >> couple of bugs >> > tracking some of the slowness issues. There is no `contract` form >> > though so I doubt that the coach will find it. >> > >> > >> http://bugs.racket-lang.org/query/?cmd=view%20audit-trail&data > base=default&pr=14610 >> > >> http://bugs.racket-lang.org/query/?cmd=view%20audit-trail&data > base=default&pr=14611 >> > >> > On Sun, Jun 29, 2014 at 11:53 AM, Jos Koot >> <jos.k...@gmail.com> wrote: >> > > Great work, Jens. I am glad my approach as been adopted >> (and much improved >> > > without deviating from the original idea of simpler >> recurrence). When can we >> > > expect it in the next nightly build? >> > > >> > > Thanks, Jos >> > > >> > >> -----Original Message----- >> > >> From: jensaxelsoega...@gmail.com >> > >> [mailto:jensaxelsoega...@gmail.com] On Behalf Of Jens >> Axel Søgaard >> > >> Sent: domingo, 29 de junio de 2014 12:48 >> > >> To: Matthew Flatt >> > >> Cc: Jos Koot; Racket Users List >> > >> Subject: Re: [racket] FW: q about code for partitions >> > >> >> > >> I have made a new vector version using zero? instead of >> exact-zero?. >> > >> >> > >> To give users a chance to remove the cache after doing >> > >> partitions calculations, >> > >> I have added set-partitions-cache. >> > >> >> > >> Code: >> > >> >> > >> https://github.com/soegaard/racket/blob/patch-14/pkgs/math-pkg >> > > s/math-lib/math/private/number-theory/partitions.rkt >> > >> >> > >> Discussion: >> > >> https://github.com/plt/racket/pull/697 >> > >> >> > >> /Jens Axel >> > >> >> > >> >> > >> 2014-06-29 12:44 GMT+02:00 Jens Axel Søgaard >> <jensa...@soegaard.net>: >> > >> > 2014-06-29 8:47 GMT+02:00 Matthew Flatt <mfl...@cs.utah.edu>: >> > >> >> It looks like "partitions2.rkt" ends up calling a >> contract-wrapped >> > >> >> variant of `exact-zero?`. >> > >> > >> > >> > That explains why Eric saw an improvement, when the used #f >> > >> instead of >> > >> > 0 as the not-cached-yet value. >> > >> > >> > >> > /Jens Axel >> > >> >> > >> >> > >> >> > >> -- >> > >> -- >> > >> Jens Axel Søgaard >> > > >> > > >> > > ____________________ >> > > Racket Users list: >> > > http://lists.racket-lang.org/users >> > >> > ____________________ >> > Racket Users list: >> > http://lists.racket-lang.org/users > > > ____________________ > Racket Users list: > http://lists.racket-lang.org/users -- -- Jens Axel Søgaard ____________________ Racket Users list: http://lists.racket-lang.org/users
