Re: [gentoo-user] About this graphite stuff

[Alex Schuster]

victor romanchuk writes:

> Alex Schuster wrote, at 01/29/2012 11:23 PM:
> > What are your impressions on this? Is it fun? Will there be a
> > noticeable speed difference? Do packages fail to build? We just had a
> > 'Graphite causing trouble' thread here, the problem was that
> > dev-libs/cloog-ppl has to be rebuilt when dev-libs/ppl has been
> > updated. Can there be other problems, which would make me waste much
> > more time than I could possibly gain by using these optimizations?
>
> i'm using graphite on core-i7 (950), x86_64 since the release of
> gcc-4.4.5 and consider it as 'just fun' - i did not observe significant
> speed difference but it should depend on a software you're going to
> 'graphitize'. things installed on my desktop are mostly for development
> (emacs, gdb, *sql, php, perl) with trivial multimedia (mplayer with
> gnome frontend), a set of web browsers and ordinary office framework:
> thunderbird, pidgin and libreoffice

I'm a KDE user, and it always felt too slow, so I thought about giving
graphite a try. Now, with the new machine, it is faster, and with 16 GB
of RAM swapping no longer occurs. So there is no longer a need for more
optimization, but I'm emerging -e @world anyway, so I think I'll just try
it.

> just for reference these are CFLAGS from my /etc/make.conf:
>
> CFLAGS="-O2 -g0 -march=core2 -msse4 -mcx16 -mpopcnt -msahf \
>         -ftree-loop-distribution -ftree-loop-linear -mmmx \
>         -floop-interchange -floop-strip-mine -floop-block -pipe"
>
> i do not use 'native' flag because that machine acts as distcc server
> for several smaller core-i<x> computers

That won't be a problem, unless the machine will be a distcc _client_. In
this case, your CFLAGS will be sent over to the distcc servers, and they
will apply _their_ native settings.
Just make sure the smaller computers don't have -march=native in their
CFLAGS, as they would get code delivered compiled for the i7.

> the only graphite incompatibility i've detected is x11-wm/compiz;
> however this is easily worked around using portage environment quirks in
> /etc/portage/env/x11-wm/compiz:
>
> CFLAGS="-O2 -g0 -march=core2 -msse4 -mmmx -pipe"
> CXXFLAGS=${CFLAGS}

I don't use that, but I guess in case I experience strange compile
problems I can always try to avoid those special CFLAGS, and it might
work.

Thanks for your input on this,

	Wonko