From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id MAA19265; Fri, 16 Aug 2002 12:41:00 +0200 (MET DST) X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id MAA19626 for ; Fri, 16 Aug 2002 12:40:59 +0200 (MET DST) Received: from fichte.ai.univie.ac.at (fichte.ai.univie.ac.at [131.130.174.156]) by nez-perce.inria.fr (8.11.1/8.11.1) with ESMTP id g7GAewj19116 for ; Fri, 16 Aug 2002 12:40:58 +0200 (MET DST) Received: (from markus@localhost) by fichte.ai.univie.ac.at (8.9.3/8.9.3/Debian 8.9.3-21) id MAA31297; Fri, 16 Aug 2002 12:40:52 +0200 Date: Fri, 16 Aug 2002 12:40:52 +0200 From: Markus Mottl To: malc Cc: Richard Nyberg , caml-list@inria.fr Subject: Re: [Caml-list] Bigarray access speed Message-ID: <20020816104052.GA31103@fichte.ai.univie.ac.at> Mail-Followup-To: malc , Richard Nyberg , caml-list@inria.fr References: <20020815225004.GA5959@gromit.it.su.se> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4i Organization: Austrian Research Institute for Artificial Intelligence Sender: owner-caml-list@pauillac.inria.fr Precedence: bulk On Fri, 16 Aug 2002, malc wrote: > Bigarrays(of at least floats) can have a slight edge over normals arrays. > To get maximal speed of the inner loops data needs to be naturally > aligned. OCaml does nothing to enforce it for non-big arrays. Bigarrays on > the other hand are mmaped(4k on IA32) and you get perfectly aligned data > for free. I was thinking that maybe Array can be extended with > make[create]_aligned, for speed/space tradeoff. Additionally, it would also be nice to have a specialized "create" function for (naturally unboxed) float arrays such that they need not be initialized with a given float value. This may be beneficial for algorithms that allocate work space whose contents is not necessarily fully needed but filled on demand. Regards, Markus Mottl -- Markus Mottl markus@oefai.at Austrian Research Institute for Artificial Intelligence http://www.oefai.at/~markus ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners