Re: gfortran, g95, and dual-core

Charles Russell wrote:
glen herrmannsfeldt wrote:
Tim Prince wrote:
> For example,(with f77 code) if the makefile
runs fsplit on a single source file, causes each subroutine to be
rebuilt separately, then combines individual objects into a single large
object, make doesn't automatically see the possibility of building the
individual objects in parallel.

Many people use nested makefiles. That is, running make from
inside the makefile. It would seem that if you ran fsplit,
then ran make on the resulting files it should be able to build
in parallel.

Is this a hypothetical "make" capable of recognizing multiprocessor
hardware and acting accordingly, or does such a thing exist now, or am I
totally confused? What tool actually does the parallelizing?
http://www.gnu.org/software/make/
I think gnu make has had the -j parallel option for close to 10 years.
As previously mentioned, it may require a pthreads library to support
parallel on Windows, so it may come down to the Cygwin implementation
for pre-built parallel capability.

Before gnu parallel make, on several operating systems, there was pmake
http://www.freebsd.org/doc/en_US.ISO8859-1/books/pmake/index.html

I'm still a little mystified that people prefer non-portable make
utilities with more difference from recognized standards. Microsoft
nmake hasn't been supported for over 3 years. The fact that only g77,
g95, and gfortran work with the built-in default rules seems less of an
obstacle to me than learning a variety of make utilities.

The fsplit example is not representative of my habits, which are to keep
all routines in separate files and put everything but the main into
static link libraries. If there is some special way to write makefiles
for f77 to make them build faster on a multicore processor, I would like
to know, but I am not sure that is what is being discussed here.

We were talking only about situations in which make parallelism isn't
automatically there. Why not simply try it on any reasonable standard
makefile?
.

Relevant Pages

  • Re: gfortran, g95, and dual-core
    ... > For example,(with f77 code) if the makefile ... then combines individual objects into a single large ... The fsplit example is not representative of my habits, which are to keep all routines in separate files and put everything but the main into static link libraries. ...
    (comp.lang.fortran)
  • Re: gfortran, g95, and dual-core
    ... Tim Prince wrote: ... > For example,(with f77 code) if the makefile ... then combines individual objects into a single large ...
    (comp.lang.fortran)
  • Re: gfortran, g95, and dual-core
    ... For example,if the makefile ... then combines individual objects into a single large ... interested in the 2 level relocatable object build. ... Compiler vendors don't advocate 2 level relocatable object builds. ...
    (comp.lang.fortran)
  • Re: gfortran, g95, and dual-core
    ... Tim Prince wrote: ... For example,(with f77 code) if the makefile ... then combines individual objects into a single large ...
    (comp.lang.fortran)