Want info on parallel makes

[Robert Claeson]

In article <464 at mtndew.UUCP>, friedl at mtndew.UUCP (Stephen J. Friedl) writes:

>      In my Allegely Portable Software Package, my focus has turned
> onto makefiles.  Some machines support a parallel make facility, and
> I would rather this it than not use it, but I don't know how common
> the syntax is.  Sequent uses the notation:

> 	target : & file1.o file2.o file3.o
> 		commands

I'm "quite" familiar (read: use it daily) with the parallel make that
Encore Computer Corp. ships with their o/s'es (BSD 4.3, SysV R3.2, Mach)
for the Multimax computers. The sequential make is named "make" and the
parallel one has the name "pmake" (I believe that there's a PD parallel
make that's also named "pmake"). Pmake doesn't require any modifications
to a well-written makefile. It recognizes when compiles aren't depending
on each other and runs them in parallel. The number of compiles that can
be performed simultaneously is determined by the environment variable
"PARALLEL", or via a command-line switch. If not given, a default of 3
is used.

Just make sure that all dependencies are explicitly defined in the
makefile. Don't rely on that a sequential make will run them in the
right order, it might not work with a parallel make, which can otherwise
start to link a program before all source files that belongs to it are
compiled.

-- 
Robert Claeson                  |Reasonable mailers: rclaeson at erbe.se
ERBE DATA AB                    |      Dumb mailers: rclaeson%erbe.se at sunet.se
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These opinions reflect my personal views and not those of my employer (ask him).