From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-2.9 required=5.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,dbe024bebf3e8f53 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2004-01-27 00:32:32 PST Path: archiver1.google.com!news2.google.com!news.maxwell.syr.edu!newsfeed.icl.net!newsfeed.fjserv.net!newsfeed.icl.net!newsfeed.fjserv.net!proxad.net!usenet-fr.net!enst.fr!melchior!cuivre.fr.eu.org!melchior.frmug.org!not-for-mail From: Stephen Leake Newsgroups: comp.lang.ada Subject: Re: [OT] Spirit - Software failure Date: 27 Jan 2004 03:30:55 -0500 Organization: Cuivre, Argent, Or Message-ID: References: <5d6fdb61.0401260215.1e460bdf@posting.google.com> <40152073$0$322$e4fe514c@news.xs4all.nl> NNTP-Posting-Host: lovelace.ada-france.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: melchior.cuivre.fr.eu.org 1075192268 30226 80.67.180.195 (27 Jan 2004 08:31:08 GMT) X-Complaints-To: usenet@melchior.cuivre.fr.eu.org NNTP-Posting-Date: Tue, 27 Jan 2004 08:31:08 +0000 (UTC) To: comp.lang.ada@ada-france.org Return-Path: In-Reply-To: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 X-Virus-Scanned: by amavisd-new-20030616-p5 (Debian) at ada-france.org X-BeenThere: comp.lang.ada@ada-france.org X-Mailman-Version: 2.1.3 Precedence: list List-Id: Gateway to the comp.lang.ada Usenet newsgroup List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Xref: archiver1.google.com comp.lang.ada:4886 Date: 2004-01-27T03:30:55-05:00 Kilgallen@SpamCop.net (Larry Kilgallen) writes: > Detailing the Spirit rover's problems. From: > http://www.cnn.com/2004/TECH/space/01/26/mars.rovers/index.html > > "Trosper said the problem appeared to be that the rover's flash memory > couldn't handle the number of files it was storing. The jam-up, she > said, apparently kept Spirit from shutting down properly and performing > a number of functions that normally originated in its flash memory. > > "Scientists are still analyzing the data, she said, but would begin > deleting unnecessary files to test that theory. > > "She pointed out that the scientists had thoroughly tested the rover's > systems on Earth, but that the longest trial for the file system was > nine days, half of the 18 days Spirit operated before running into the > problem." > -------------------- > Perhaps this is the first time that a defrag actually fixes something? > Deleting files isn't defrag. This report describes a plain old memory leak. Which probably would have been checked for if they had called the software managing the flash ram a "memory management system" rather than a "file system"; JPL programmers know they need to check for memory leaks. But apparently they don't know they need to check for full disks? How long does a test need to be to be "thorough"? Longer than 9 days, apparently :). I doubt using Ada would have fixed this. They'd have just mapped Ada.Text_IO to the flash memory, and had the same problem :). Hiding dynamic memory management under a file system metaphor is a bad idea in so many ways ... -- -- Stephe