[yocto] Multiple MACHINEs in a single build?

[Khem Raj]

On Thu, May 5, 2016 at 12:20 PM, Marcelo E. Magallon
<marcelo.magallon at hpe.com> wrote:
> On Thu, May 05, 2016 at 06:45:36AM -0700, Khem Raj wrote:
>
>> > This works:
>> >
>> >     $ MACHINE=qemux86 bitbake core-image-minimal
>> >     $ MACHINE=qemux86-64 bitbake core-image-minimal
>> >
>> > and bitbake parallelizes the build across tasks. What I'm trying to
>> > figure out is if it's possible to run two bitbake instances with
>> > different MACHINE values on different hosts but writing to the same
>> > workspace (say, over NFS).
>>
>> Thats not possible and its by design.
>
> Can you nudge me in the direction of some documentation for this design?

It was not a conscious choice to limit however that is what it started with
single machine singe distro in one invocation. It has been raised in
past and I was
one of the persons who raised it as a limitation if you want to call it.

However in your case you said NFS and we have seen problems with NFS even with
single machine builds in past so just be aware. Secondly during build
there are native
packages built and staged and every machine will build them similarly
there are all-*-*
packages which are going to conflict if two bitbake instances did not
synchronise, they
might conflict with each other, so unless we change the logic to let
bitbake take machine
as parameter and setup global datastore accordingly e.g.

bitbake machine1,<image1, images2,.,,, machine2,<imageA, imageB....>

it might not work.

>
> Thanks!
>
> Marcelo