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=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,e0e1d3b3f7c994b8 X-Google-Attributes: gid103376,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news3.google.com!feeder3.cambrium.nl!feed.tweaknews.nl!newsfeed.kamp.net!newsfeed.kamp.net!news.unit0.net!newsfeed.straub-nv.de!proxad.net!feeder1-2.proxad.net!fdn.fr!news.wanadoo.fr!news.wanadoo.fr!not-for-mail Message-ID: <47D3FA43.4060906@obry.net> Date: Sun, 09 Mar 2008 15:54:59 +0100 From: Pascal Obry Organization: Home - http://www.obry.net User-Agent: Thunderbird 2.0.0.12 (Windows/20080213) MIME-Version: 1.0 Newsgroups: comp.lang.ada To: Maciej Sobczak Subject: Re: Robert Dewar's great article about the Strengths of Ada over other langauges in multiprocessing! References: <13t4b2kkjem20f3@corp.supernews.com> <89af8399-94fb-42b3-909d-edf3c98d32e5@n75g2000hsh.googlegroups.com> <47D39DC8.20002@obry.net> <426fb20b-2897-4751-9d2f-239221cfb987@m44g2000hsc.googlegroups.com> In-Reply-To: <426fb20b-2897-4751-9d2f-239221cfb987@m44g2000hsc.googlegroups.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit NNTP-Posting-Date: 09 Mar 2008 15:55:02 CET NNTP-Posting-Host: 82.120.154.23 X-Trace: 1205074502 news.orange.fr 890 82.120.154.23:3786 X-Complaints-To: abuse@orange.fr Xref: g2news1.google.com comp.lang.ada:20260 Date: 2008-03-09T15:55:02+01:00 List-Id: Maciej, > I've seen 80x (eighty times) penalty when comparing Ada's protected > objects with basic usage of mutexes in C++. > 80x is not something to be taken lightly. I've never seen such penalty. Maybe in theory or in a very specific part of the code. But let's compare the *final* application speed. I have gone this path in a medium simulation, the Ada implementation was slower in some part, the C++/OpenMP implementation was slower on some other part. The final application was running at same speed in Ada and C++ (well in fact the Ada implementation was a bit less than 1% faster than the C++ one). Also, one point about the C++/MPI version (we also worked on a distributed version even if I don't have the final data, but speed was almost comparable) compared to the Ada Annex-E version. My co-worker were amazed at how fast I was able to re-configure the distributed application. Where it took days/weeks to change the MPI implementation, it took me hours to change the GLADE configuration file. Also, the facility to exchange Ada Containers objects across partitions was pretty amazing. No tweak, no hack, clean code, just plain Ada. I know a group of C++ hackers still trying to come up with a clean solution to exchange objects (class instance) across nodes... Impossible to stream properly objects in C++, or you have to code almost all by hand! All these aspects are far more important to me than pure speed. I understand that this tradeoff can be different on some other applications, but I won't buy that this is majority of cases! Pascal. -- --|------------------------------------------------------ --| Pascal Obry Team-Ada Member --| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE --|------------------------------------------------------ --| http://www.obry.net --| "The best way to travel is by means of imagination" --| --| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595