Re: [gentoo-dev] Portage QOS

Tom Wijsman <TomWij@g.o> writes:

>> I am curious about the slowness of emerge.
>
> Try a --backtrack=0 approach, I no longer need to increase it. :)

on a random box:

time emerge --backtrack=0 -pe @world
[...]
real    0m30.016s
user    0m29.268s
sys     0m0.704s

time emerge -pe @world
[...]
real    0m35.037s
user    0m30.824s
sys     0m1.136s

not a big difference?

>> How about profile the portage and rewrite the time-crucial part in
>> C/C++, or ideally, borrowing the counterpart from paludis? How
>> feasible is that?
>
> http://dev.gentoo.org/~tomwij/files/portage-2.2.7-python-2.7-backtrack-0.png
> http://dev.gentoo.org/~tomwij/files/portage-2.2.7-python-2.7-backtrack-0-hot.png
> http://dev.gentoo.org/~tomwij/files/portage-2.2.7-python-3.3-backtrack-0.png
>
> (hot is the hotshot profiler, it internally checks on the line level
> instead; 3.3's profiler is obstructed by module loading, no idea why)

Great! That's what I am looking for.