[oe] PARALLEL_MAKE

[Tom Rini]

On Tue, Mar 17, 2009 at 05:28:27PM +0100, Ulf Samuelsson wrote:
[snip]
> BTW: The total buildtime was around 2 hours. There is some overhead
> since the build was restarted 3-4 times, and local.conf was changed once.
> I started the build with PARALLEL_MAKE = "-j2" and BB_NUMBER_THREADS=8.

Hmm.  I wonder if the gettext problem was related to having so many
threads.  For my builds I had been getting around 2 hours (once sources
are fetched), but as I've said, I do -j8/4 threads.  I haven't yet
expirimented with my new box, so I'll give a j2/8 threads one a shot and
see where gettext is falling down.

> I noticed that having a lot of threads helps most of the time,
> since the CPUs were executing at max frequency.
>
> When the cross compiler, was built,it was different,
> most of the cores were not used with this configuration.
> 2-3 max while compiling gcc.

Yeah.  I almost wonder if it's worth doing some python string magic to
try and manually bump up PARALLEL_MAKE in recipes that we know are
bottlenecks.

-- 
Tom Rini