Can the port command take advantage of multiple cores?

[Anders F Björklund]

Ryan Schmidt wrote:

>>     Ryan> As ports are tested, "use_parallel_build yes" is added to 
>> the
>>     Ryan> portfile. Then MacPorts will build those ports using -j$jobs
>>     Ryan> (where $jobs is the number of CPU cores in your computer). 
>> This
>>     Ryan> was added for MacPorts 1.6.
>>
>> Excellent, thanks.  That makes it transparent even. ;-)
>
> Well, that's what I thought happened. But now others are saying 
> there's an option in macports.conf that needs to be set. Can someone 
> please clarify? Is there an option, and if so, what does it need to be 
> set to?

There is a config parameter in macports.conf called "buildmakejobs",
that controls the default value for build.jobs (default config is 1)

However, this was considered dangerous so the Portfile opt-in setting
of "use_parallel_build" was added - with a default setting of no.


So in order to get MacPorts to use -j2 or more, you need to both
set your local preference and then also each Portfile to opt-in...

Opt-in was added in 
http://trac.macports.org/projects/macports/changeset/30714
before that it assumed opt-out -(by using "build.jobs 1") instead.

--anders