Re: build farm machine using <make -j 8> mixed results

On Sat, 2012-09-08 at 19:54 -0400, Tom Lane wrote:
> Anyway, what I notice is that I get different types of failures, but
> they are all under ecpg/. What I think we need to do is insert
> .NOTPARALLEL in ecpg/Makefile,

I'd hate that, because the ecpg build is one of the slowest parts of the
build, so de-parallelizing it would slow down everything quite a bit.

> because there are several reasons not
> to run its sub-makes in parallel:
>
> * preproc/Makefile casually does this:
>
> ../ecpglib/typename.o: ../ecpglib/typename.c
> $(MAKE) -C $(dir $@) $(notdir $@)
>
> which is very likely to screw up any make proceeding in parallel in
> ecpglib.

That should probably be fixed by symlinking the source file and building
it in the preproc directory.

> And that's not even counting the bison-output problem you were seeing.
> I'm not entirely sure what's causing that, but I'm suspicious that the
> ultimate cause is the extra rules for the "all...recurse" targets in
> ecpg/Makefile, which look like they could result in additional instances
> of multiple make processes running in the same subdirectory.

I think the point of these targets is exactly to prevent that.