Re: Parallel build not working since -test6?

["Adam Kropelin" <akropel1@rochester.rr.com>]

Derek Foreman <manmower@signalmarketing.com> wrote:
> On Fri, 28 Nov 2003, Sam Ravnborg wrote:
> 
>> On Thursday 27 November 2003 00:27, Adam Kropelin wrote:
>>> Lately I've noticed my kernel compilations taking longer than usual.
>>> Tonight I finally realized the cause... Parallel building (i.e.
>>> make -jN) is no longer working for me. I traced it back and the
>>> last kernel it worked in was -test5. It ceased working in -test6.
>> It works for me, and for sure it works for most others. Otherwise I
>> would have seen lot of complaints like yours.
>> I recall one similar post, and the person in question used a
>> homegrown script that caused the problems.
> 
> Well, this explains why 2.6.x builds so much slower here than it did
> a few kernels ago.
> 
> make -j3 improves things.  but currently, make -j2 doesn't use both my
> cpus.
> 
> no scripts, just make -j2 bzImage

Ah, yes... -j3 gets me 2 cpp/cc pairs as well. 

What I see with -j3 is 1 parent make process and two make child processes.
With -j2 I see one parent and one child. Leaving -j off entirely gives the same
as -j2. 

-j3:
root     25314 15539  0 Nov27 tty1     00:00:00 make -j3 bzImage
root     25545 25314  0 Nov27 tty1     00:00:00 make -f scripts/Makefile.build obj=arch/i386/kernel
root     25814 25314  0 Nov27 tty1     00:00:00 make -f scripts/Makefile.build obj=kernel


-j2:
root     26391 15539  0 Nov27 tty1     00:00:00 make -j2 bzImage
root     26582 26391  0 Nov27 tty1     00:00:00 make -f scripts/Makefile.build obj=init


--Adam