Re: What are the key factors for yocto build speed?


Yann Dirson
 



Le jeu. 19 mars 2020 à 17:07, Mike Looijmans <mike.looijmans@...> a écrit :
On 19-03-2020 12:04, Richard Purdie via Lists.Yoctoproject.Org wrote:
>> , fetch, configure, package and rootfs tasks.
>
> Sadly these tasks are much harder.

It would be really great if some sort of "weight" could be attached to a
task. This relates to memory usage.

My system has 16 cores but only 8GB RAM. With both parallelization
options to "16", I might end up with 16 compile tasks running 16 compile
threads each, i.e. 256 running processes. In practice this doesn't
actually happen, but the memory load gets high sometimes, so I reduce
the TASKS to 8 at most. That has kept my system out of swap trouble for
the time being.

This could be neatly handled by using the GNU-make job-server mechanism.
If bitbake itself would provide a jub-server, all make-based recipes would
automatically get their jobs properly limited.  There is a (sadly not merged yet)
MR [1] for ninja tu gain job-server support as well, through which we should have
a pretty good coverage of the recipes set (as a backend for cmake, meson, and more).


--
Yann Dirson <yann@...>
Blade / Shadow -- http://shadow.tech

Join yocto@lists.yoctoproject.org to automatically receive all group messages.