From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Rob Browning Newsgroups: gmane.lisp.guile.devel Subject: Re: gmp issues (long) Date: Tue, 25 Feb 2003 14:08:41 -0600 Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Message-ID: <87adgkt96e.fsf@raven.i.defaultvalue.org> References: <200302251332.32383.s11@member.fsf.org> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: main.gmane.org 1046203838 7332 80.91.224.249 (25 Feb 2003 20:10:38 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Tue, 25 Feb 2003 20:10:38 +0000 (UTC) Cc: guile-devel@gnu.org Return-path: Original-Received: from monty-python.gnu.org ([199.232.76.173]) by main.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 18nlP6-0001tI-00 for ; Tue, 25 Feb 2003 21:10:16 +0100 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.10.13) id 18nlNp-0008D0-00 for guile-devel@m.gmane.org; Tue, 25 Feb 2003 15:08:57 -0500 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.10.13) id 18nlNf-0008By-00 for guile-devel@gnu.org; Tue, 25 Feb 2003 15:08:47 -0500 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.10.13) id 18nlNd-0008BC-00 for guile-devel@gnu.org; Tue, 25 Feb 2003 15:08:46 -0500 Original-Received: from dsl093-098-016.wdc1.dsl.speakeasy.net ([66.93.98.16] helo=defaultvalue.org) by monty-python.gnu.org with esmtp (Exim 4.10.13) id 18nlNd-0008Ai-00 for guile-devel@gnu.org; Tue, 25 Feb 2003 15:08:45 -0500 Original-Received: from raven.i.defaultvalue.org (raven.i.defaultvalue.org [192.168.1.7]) by defaultvalue.org (Postfix) with ESMTP id 891C3A9DC; Tue, 25 Feb 2003 14:08:41 -0600 (CST) Original-Received: by raven.i.defaultvalue.org (Postfix, from userid 1000) id 6BFC0D0004; Tue, 25 Feb 2003 14:08:41 -0600 (CST) Original-To: Stephen Compall In-Reply-To: <200302251332.32383.s11@member.fsf.org> (Stephen Compall's message of "Tue, 25 Feb 2003 13:32:17 -0600") User-Agent: Gnus/5.090008 (Oort Gnus v0.08) Emacs/21.2 (i386-pc-linux-gnu) X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1b5 Precedence: list List-Id: Developers list for Guile, the GNU extensibility library List-Help: List-Post: List-Subscribe: , List-Archive: List-Unsubscribe: , Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: main.gmane.org gmane.lisp.guile.devel:1973 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:1973 Stephen Compall writes: > Rob Browning wrote: > replace the _mp_size field with a short, since I doubt that we'd > ever be likely to overflow long data[MAX_SHORT] digits. (What was > the size limit, if any, on our old bignums?). > > My first use of GMP in C (after the requisite playing around while > learning) was to try to build up a Godel number as an example in a > project involving semigroups I'm working on (OT). After creating one of > these numbers, I believe the memory usage of the mpz_t & friends was ~5 > MB. While this was an abnormal case, it's still far off from 256k. > er.... Wow. That's a pretty giant number :> OK. If we want to accomodate numbers this big without a 2-tier hybrid approach, or something, people should adjust my storage computations to account for a 4-byte size rather than a 2-byte-size. Also, just for comparison, and presuming I read the code correctly, our previous implementation used a 16-bit (plus sign bit) size field, so moving to a 4-byte size field would be a substantial increase over what we supported before. -- Rob Browning rlb @defaultvalue.org, @linuxdevel.com, and @debian.org Previously @cs.utexas.edu GPG starting 2002-11-03 = 14DD 432F AE39 534D B592 F9A0 25C8 D377 8C7E 73A4 _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://mail.gnu.org/mailman/listinfo/guile-devel