Subject: Re: Have pkgsrc building make use of SMP?
To: Hubert Feyrer <hubert@feyrer.de>
From: Lars Nordlund <lars.nordlund@hem.utfors.se>
List: tech-pkg
Date: 04/05/2005 23:51:47
Tue 2005-04-05 klockan 23:12 +0200 skrev Hubert Feyrer:
> On Tue, 5 Apr 2005, Lars Nordlund wrote:
> > It would be really cool to be able to just have pkgsrc build multiple
> > packages at the same time.
> 
> Do you understand the difference of your suggestion to mine?

Sure.

> Why do you think running the whole pkgsrc infrastructure on two cpus in 
> parallel (with all the cache impact etc.), and adding the necessary 
> locking infrastructure to ensure dependencies are built before 
> applications that need them is better than just go and utilize all CPUs 
> with the compiler (which is already in cache) for all the CPUs in 
> parallel, and go for building one thing after another?
> 
> If you're keen on debugging such locking problems, why not have a 
> look at why make has issues with make -jX (X>1)?

>From what I have seen it is quite common for packages to not be make -j
safe. Securing those will take time.

On the other hand it is no problem building several packages from pkgsrc
at once, given their dependancy list does not clash (and PKGSRC_LOCKTYPE
will kick in, but this will of course just utilize one CPU since the
other build process is sleep waiting for the first one to finish).

Don't you ever build for example emacs and xmms at the same time, given
that you already have X and possibly other basic packages installed? 


	/Lars