options for compiling large jars

Sat Dec 16 18:00:00 GMT 2006

Andrew Haley wrote:
> > I can understand that, because it because when I compile
> > kawa.jar without optimization it is fairly quick (2m17s),
> > but when I compile with -O1 it takes forever.
> > Even using -fno-unit-at-a-time doesn't seem to help.
>> You're short of RAM? AFAICS compiling with optimization takes about
> three times as long as compiling without, as long as you don't run
> short of RAM.

That is presumably the problem. I have 1Gb on my primary development
laptop, and similar amounts (0.5G - 2Gb, I think - what's an easy way
to check a running Fedora system?) on my other computers.
But I don't think it is acceptable not being able to build Kawa
in a reasonable time using a 1Gb machine ...
(If gcc used more memory- and locality-efficient data structures
we could probably do whole-program compilation of large programs
without swapping. But that is a different discussion.)
> > What I've done with Kawa before is compile one package
> > at a time, and that seems to work fairly well.
> > But I'm trying to figure out what changes are appropriate
> > in the new world, where we use ecj and gcj-dbtool.
>> You can continue to compiler things in the same way, as long as you
> use -findirect-dispatch and -Bsymbolic.

Ok, I'll do that.
-- 
	--Per Bothner
per@bothner.com http://per.bothner.com/