Re: is anyone using threaded automake?

[Ralf Wildenhues]

Hi Jason,

* Jason Sewall wrote on Sun, Nov 01, 2009 at 06:28:31PM CET:
> On Sun, Nov 1, 2009 at 6:45 AM, Ralf Wildenhues wrote:
> >
> > Is anyone using it?  Has anyone seen issues with it?
> 
> I didn't even know it existed, but I just tried it out and it seems to
> generate correct output for a project I have with 12 Makefile.am
> files. I have a quad core machine and set AUTOMAKE_JOBS=4.
> 
> The performance gains are fairly small, however:
> $ AUTOMAKE_JOBS=1 time automake
> 1.31user 0.19system 0:01.51elapsed 100%CPU
> 
> $ AUTOMAKE_JOBS=4 time automake
> 1.62user 0.24system 0:01.14elapsed 163%CPU

Yeah, the perl thread spawning really has high overhead, and the output
synchronization isn't all that performant either.  I did get quite
acceptable speedup out of a 150-makefile project.

> And they are imperceptible with autoreconf.

Oh well.

Thanks for testing,
Ralf