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-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,718bd701b6b36346 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-08-13 06:44:27 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!bloom-beacon.mit.edu!micro-heart-of-gold.mit.edu!news-out.nuthinbutnews.com!propagator-sterling!news-in.nuthinbutnews.com!falcon.america.net!eagle.america.net.POSTED!not-for-mail Message-ID: <3D590D80.201@otelco.net> From: Larry Hazel User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.0rc2) Gecko/20020618 Netscape/7.0b1 X-Accept-Language: en,x-ns11F8K63r3NhQ,x-ns2r2e09O MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: GNAT/Ada95 Streams Performance Issue References: <3D51ECC9.8020406@cogeco.ca> <3D585F63.6010205@otelco.net> <5ee5b646.0208130025.41805ea8@posting.google.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 13 Aug 2002 08:45:36 -0500 NNTP-Posting-Host: 66.0.32.230 X-Trace: eagle.america.net 1029246288 66.0.32.230 (Tue, 13 Aug 2002 09:44:48 EDT) NNTP-Posting-Date: Tue, 13 Aug 2002 09:44:48 EDT Organization: 24hoursupport.com Xref: archiver1.google.com comp.lang.ada:27977 Date: 2002-08-13T08:45:36-05:00 List-Id: Robert Dewar wrote: > Larry Hazel wrote in message news:<3D585F63.6010205@otelco.net>... > > >>Somewhere around 1990, I wrote a simple file copy program >>using Sequential_IO on >>files of bytes. > > > Note that there is no portable way of doing this in either > Ada 83 or Ada 95. In practice, instantiating SIO for type > Character would probably work. > > >>This was using the Verdix Ada 83 compiler on a Sun. I >>did this as a test because C people kept telling me how >>slow Ada was. I wanted to see for myself. >>It was consistently faster than the unix cp command. > > > Hard to believe, and if true, simply a comment on a truly > appalling implementation of cp. > > >>I suspect there was a >>lot of buffering going on behind the scenes. > > > That's not enough to account for this surprising result! Robert, After reading your reply and trying to remember what I did, I think the byte SIO program was the first attempt and not very fast. I vaguely remember doing something with direct io and large arrays of bytes for the program that was faster than cp. Larry