Re: [gentoo-portage-dev] Cache rewrite backport

[Brian Harring]

On Wed, Oct 12, 2005 at 02:56:38PM +0200, Bastian Balthazar Bux wrote:
> Brian Harring ha scritto:
> > Rather then keep posting large patches here, just going to post them
> > to dev.gentoo.org/~ferringb/portage/2.0 ... for example,
> > http://dev.gentoo.org/~ferringb/portage/2.0/3.0-cache-backport-experimental-4.patch
> >
> > should be pulled rather then previous patch.
> >
> > Helluva lot easier for me since I can correct dumb ass mistakes like
> > an import pdb for testing sliding into a patch :)
> >
> > Think that's probably a sign it's time for some sleep...
> > ~harring
>
> premessa:
> emerge metadata does not recreate the cache after a
> "rm -rf $PORTDIR/metadata/cache/*" .
> The first thing that came in mind is that I'm missing something obvious.
Can't trigger that myself... so would be curious.

> Today working on a different box, slower cpu, faster disk (ratio 2:1)
>
> sys-apps/portage-2.0.53_rc5 patched version
> time emerge --metadata three times, first time with error trace
> real    3m43.162s 0m14.986s 0m14.124s
> user    0m13.580s 0m10.790s 0m11.150s
> sys     0m7.990s  0m3.280s  0m2.960s
>
> sys-apps/portage-2.0.53_rc5 vanilla
> time emerge --metadata three times
> real    0m47.913s 0m52.677s 0m37.448s
> user    0m32.900s 0m31.720s 0m31.870s
> sys     0m7.020s  0m6.440s  0m5.530s
>
> sys-apps/portage-2.0.53_rc5 patched version again
> time emerge --metadata three times, first time with error trace
> real    0m17.386s 0m14.029s 0m13.873s
> user    0m12.110s 0m10.980s 0m10.820s
> sys     0m3.950s  0m3.020s  0m3.040s
>
> =================== cache file example
> cat $PORTDIR/metadata/cache/sys-apps/portage-2.0.53_rc5
> >=dev-lang/python-2.2.1
> !build? ( >=sys-apps/sed-4.0.5 dev-python/python-fchksum
> >=dev-lang/python-2.2.1 userland_GNU? ( sys-apps/debianutils )
> >=app-shells/bash-2.05a ) !userland_Darwin? ( sys-apps/sandbox )
> selinux? ( >=dev-python/python-selinux-2.15 )
> 0
> mirror://gentoo/portage-2.0.53_rc5.tar.bz2
> http://dev.gentoo.org/~jstubbs/releases/portage-2.0.53_rc5.tar.bz2
>
> http://www.gentoo.org/
> GPL-2
> The Portage Package Management System. The primary package management
> and distribution system for Gentoo.
> ~alpha ~amd64 ~arm ~hppa ~ia64 ~m68k ~mips ~ppc ~ppc-macos ~ppc64 ~s390
> ~sh ~sparc ~x86
> multilib toolchain-funcs
> build selinux

^^^ that's a flat_list entry, if/when this faster code is deployed a 
wipe of the cache probably would occur since flat_list and flat_hash 
use the same location (need to change that someday imo).

Explains the traceback that followed. :)

_Still_ need to modify the damn thing to cover another angle for 
PORTDIR being wholesale moved, but posted an experimental-6 that will 
be a bit slower, but is a bit more correct about handling the cases 
above, and dealing with eclass staleness checks.
~harring