RE: Speeding up ATLAS build time

[R Clint Whaley <rwhaley@cs.utk.edu>]

Carl,

Just a few boneheaded questions . . .

First, it looks like -j does not work with SunOS or AIX or IRIX make.  Can
anyone with some knowledge of these guys comment (I don't have access to
their man pages at present)?  Since gnu make is often used on these systems,
it's not a killer, but surely they have an equivalent?

>"make -j N" it is set to "make -j n" where "n"
>is 2 * ncpu.

Why is it 2*ncpu rather than ncpu?  Is -j 2 more efficient than no -j on
a serial machine?

>Then I went through all the makefiles in "makes"
>and edited them to use $(PMAKE) to build object
>files, usually by moving the object files from
>the dependency line to a $(PMAKE) line in the
>target build section.

But the dependency information is not lost, right?  For instance, it is
still true that already-built libs will not be rearchived, and that missing
files will be compiled, yes?

Sorry to send questions rather than just scoping the stuff, but I'm afraid
time constrainsts mean that I will probably want to scope it out once you
have the whole thing working and debugged, just to avoid spending the time
several times, even though I realize the process would be helped by doing
it iteratively . . .

Thanks,
Clint