Re: [OE-core] [PATCH 1/3] ptest.bbclass: Honor PARALLEL_MAKE, PARALLEL_MAKEINST

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Wed, 2022-06-22 at 22:16 +0300, niko.mauno@vaisala.com via
lists.openembedded.org wrote:
> Since oe_runmake wrapper doesn't by default involve PARALLEL_MAKE
> outside do_compile() nor PARALLEL_MAKEINST outside do_install(),
> enable parallellized make by default when oe_runmake is invoked from
> do_compile_ptest() or do_install_ptest() by declaring wrapper task
> specific EXTRA_OEMAKE overrides in fashion similar to do_compile and
> do_install overrides in meta/conf/bitbake.conf.
> 
> Parallel make can still be disabled by resetting bbclass specific
> PTEST_PARALLEL_MAKE and PTEST_PARALLEL_MAKEINST variables in recipe
> e.g. if a race issue needs to be avoided without modifying source code.
> 
> Tested by issuing following command sequence on a 32-core build host:
> 
>   $ bitbake -c clean util-linux && bitbake --skip-setscene -c compile util-linux && time bitbake --skip-setscene -c compile_ptest_base util-linux
> 
> and found that before this change the result was
> 
>   real	0m34.684s
>   user	0m0.753s
>   sys	0m0.131s
> 
> and after this change
> 
>   real	0m9.868s
>   user	0m0.749s
>   sys	0m0.150s
> 
> Signed-off-by: Niko Mauno <niko.mauno@vaisala.com>
> ---
>  meta/classes/ptest.bbclass | 4 ++++
>  1 file changed, 4 insertions(+)

This has merged but is causing a few problems. So far, elfutils and
flex both ran into make races with a ton of failed builds as a result.
I've a patch to disable paralell compile for those two recipes in the
ptest compile. Ideally we'd look into and get this issues fixed
upstream.

Some random build failure links (there are many more in that build):

https://autobuilder.yoctoproject.org/typhoon/#/builders/100/builds/3045
https://autobuilder.yoctoproject.org/typhoon/#/builders/65/builds/5446
https://autobuilder.yoctoproject.org/typhoon/#/builders/62/builds/5417
https://autobuilder.yoctoproject.org/typhoon/#/builders/95/builds/3428

Cheers,

Richard