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From: guy@sun.uucp (Guy Harris)
Newsgroups: net.lang.f77,net.unix,net.unix-wizards,net.lang
Subject: Re: Any decent Fortrans under Unix ? Which machine ?
Message-ID: <3274@sun.uucp>
Date: Sun, 23-Feb-86 02:55:24 EST
Article-I.D.: sun.3274
Posted: Sun Feb 23 02:55:24 1986
Date-Received: Wed, 26-Feb-86 04:03:05 EST
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Xref: linus net.lang.f77:409 net.unix:6628 net.unix-wizards:14095 net.lang:1927

> 	The Fortran users are unwilling to consider an Unix solution because
> they believer that Fortran performance under Unix is woefully inadequate. I
> have heard many informal reports to this effect and it certainly seems to be
> firmly embedded in the folklore of Unix.

As are a number of other incorrect or misleading claims.  There is no such
thing as "FORTRAN performance under UNIX".  Which FORTRAN?  Which UNIX?
From what I can glean from some postings, DEC offers both the 4.3BSD "f77",
which is descended from the original UNIX "f77" but has had a lot of effort
put into optimization, and the VMS FORTRAN 77 compiler under ULTRIX.  The
latter probably offers excellent performance, and the former is probably
fairly good as well.  Sun has a FORTRAN which is also descended from the
original UNIX "f77", but which has had a new optimizer added; it is claimed
to offer comparable performance with VMS FORTRAN 77.  A number of the
"minisupercomputer" vendors have vectorizing FORTRAN compilers for their
UNIX.  I think Gould has brought up their own FORTRAN under their UNIX, and
I presume Apollo's FORTRAN is not "f77"-based and is fast.

On the other hand, if you get a PDP-11 and run the original "f77" that came
with V7, the performance will probably be dismal compared to, say, FORTRAN
IV-PLUS.  A lot of UNIX box vendors have probably put little effort into
software other than porting and some bug fixing, and probably have equally
low-performance FORTRANs.  ("f77" was originally done because Stu Feldman
wanted to see if you could do a FORTRAN compiler using the UNIX C compiler's
code generator - it was a research project, not a production compiler.)

The low performance of the original "f77"s generated code is probably what
gave rise to this folklore, but not all UNIX FORTRAN compilers are
"f77"-based and the "f77"-based ones from serious vendors have had serious
effort put into making "f77" generate high-quality code.

Tell the FORTRAN users that blindly believing folklore may require little
effort but doesn't bring very much in the way of rewards, either.
-- 
	Guy Harris
	{ihnp4, decvax, seismo, decwrl, ...}!sun!guy
	guy@sun.arpa	(yes, really)