Re: [CFT] build: WITH_FAST_DEPEND and WITH_CCACHE_BUILD

On Thu, Nov 12, 2015 at 9:40 AM, Bryan Drewery <bdrewery_at_freebsd.org> wrote:

> - The first is WITH_FAST_DEPEND. Please see the commit for its full
>

I have enabled WITH_FAST_DEPEND in make.conf for several builds.

(1)     Job: https://jenkins.freebsd.org/job/FreeBSD_HEAD
         Before WITH_FAST_DEPEND:
https://jenkins.freebsd.org/job/FreeBSD_HEAD/3488/    1 hour, 23 minutes
         After WITH_FAST_DEPEND:
https://jenkins.freebsd.org/job/FreeBSD_HEAD/3497/ ,      1 hour, 17 minutes

         Compiler used: clang

(2)   Job: https://jenkins.freebsd.org/job/FreeBSD_HEAD_sparc64/
        Before WITH_FAST_DEPEND:
https://jenkins.freebsd.org/job/FreeBSD_HEAD_sparc64/1309/ , 23 minutes
        After WITH_FAST_DEPEND:
https://jenkins.freebsd.org/job/FreeBSD_HEAD_sparc64/1329/ , 22 minutes

        Compiler used: gcc 4.2.1

(3)  Job: https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc4.9/
       Before WITH_FAST_DEPEND:
https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc4.9/761/ , 1 hour, 7
minutes
       After WITH_FAST_DEPEND:
https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc4.9/762/ , 1 hour 2
minutes

       Compiler:  gcc 4.9.2

The timings are not very scientific, because the VM's in which the builds
are occurring are
very loaded, since each build host is running multiple VM's, which are
building different things.

This gives you a basic idea though, that WITH_FAST_DEPEND works on a few
compilers (clang, gcc 4.2, gcc 4.9),
and there is some build time reduction, and no increase in build time.

Congratulations for tackling this stuff in FreeBSD.  As you mentioned, this
area has not been touched
in 14 years.
--
Craig