Speed up build phase with "make -j"

[Markus Weissmann]

On 31.10.2007, at 05:13, Vincent Lefevre wrote:

> On 2007-10-30 16:20:18 +0100, Markus Weissmann wrote:
>> On 30.10.2007, at 13:52, Vincent Lefevre wrote:
>>> The bug could also be reported upstream, so that a ".NOTPARALLEL:"
>>> is added to the Makefile.
>>
>> Well, this simply is not going to work -- this has to be an opt-in,
>> not an opt-out option!
>
> That's not the point. Whether MacPorts uses a parallel build by  
> default
> or not, a Makefile should be correct (either by supporting parallel
> build or by having a ".NOTPARALLEL:"). If it is not, this is a bug.
> If such bugs are not reported upstream, you're not going anywhere
> (experience shows that in general, upstream doesn't test parallel
> builds).
>
>> If you do not know if a parallel build will work for a port, you must
>> assume it won't.
>
> I disagree. Port maintainers should test their port to see if they  
> work
> with "make -j".
>

Well, you cannot reliably test this. If you're lucky it might work  
one time and fail the other.


>> Once upon a day when we see that 80% of our ports all have that
>> "build_in_parallel yes" option set, we can make it the default, but
>> not as long as only _very_ few do.
>
> Yes, but how can you hope that 80% of ports will have
> "build_in_parallel yes" if one assumes that parallel build doesn't  
> work?
>

I didn't say I assume this to be the case one day, it was more of an  
utopian perspective; one that currently is not true for sure.
The point is that ports that are not given 110% love (e.g.  
unmaintained ones, busy maintainers) will simply break -- probably in  
spectacular non-deterministic ways.


-Markus

--
Markus W. Weissmann
http://www.mweissmann.de/