+1 for this being opt in. It's a substantial hit to build time On Thu, Aug 23, 2018 at 12:21 PM Christopher Larson <kerg...@gmail.com> wrote:
> IMO PGO should really stay opt-in, not opt-out, given the performance > impact. > > On Thu, Aug 23, 2018 at 1:28 AM Richard Purdie < > richard.pur...@linuxfoundation.org> wrote: > >> On Wed, 2018-08-22 at 18:44 -0700, Andre McCurdy wrote: >> > On Thu, Aug 16, 2018 at 9:48 PM, Anuj Mittal <anuj.mit...@intel.com> >> > wrote: >> > > On 08/17/2018 03:31 AM, Andre McCurdy wrote: >> > > > On Wed, Aug 15, 2018 at 11:26 PM, Anuj Mittal <anuj.mittal@intel. >> > > > com> wrote: >> > > > Is it important to re-create the profile data during every build >> > > > or >> > > > would we get most of the same benefits from using reference data >> > > > which >> > > > is generated offline? >> > > >> > > We should get the same benefit using the data generated offline as >> > > long >> > > as the source code/configure options/flags are same I believe. I >> > > have >> > > only tried with data generate offline using the same build >> > > configuration >> > > though. >> > >> > As an additional data point, python do_compile now takes approx 18 >> > minutes on my laptop. A single qemu-i386 thread loading one CPU core >> > at 100%, with nothing else being scheduled in parallel for most of >> > that time. >> > >> > If we can get most of the benefits of pgo with a pre-generated data >> > file then that might still be something to explore. >> >> I've also noticed the increased build times. I'd love to see if we >> could create an sstate object which would contain the pgo data and >> which didn't depend on the usual compiler/toolchain pieces, only the >> do_patch stage checksum. In theory, the same sstate object should be >> reusable between target/native/nativesdk too as long as we had the same >> python patchset (which I know we don't for native). >> >> Anyone fancy such a challenge? We should probably have a bug open for >> this at least... >> >> Cheers, >> >> Richard >> >> -- >> _______________________________________________ >> Openembedded-core mailing list >> Openembedded-core@lists.openembedded.org >> http://lists.openembedded.org/mailman/listinfo/openembedded-core >> > > > -- > Christopher Larson > kergoth at gmail dot com > Founder - BitBake, OpenEmbedded, OpenZaurus > Senior Software Engineer, Mentor Graphics > -- > _______________________________________________ > Openembedded-core mailing list > Openembedded-core@lists.openembedded.org > http://lists.openembedded.org/mailman/listinfo/openembedded-core >
-- _______________________________________________ Openembedded-core mailing list Openembedded-core@lists.openembedded.org http://lists.openembedded.org/mailman/listinfo/openembedded-core