Re: [gentoo-dev] Do we want optimal performance?

[Paul de Vrieze <pauldv@gentoo.org>]

[-- Attachment #1: Type: text/plain, Size: 2169 bytes --]

On Wednesday 08 September 2004 21:11, Klavs Klavsen wrote:
> Chris Gianelloni said:
> [SNIP]
>
> > Gentoo is not all about performance.  While many of our users want to
> > squeeze the every drop of performance out of their systems, many use
> > Gentoo for any number of other reasons such as our philosophy, our
> > community, the manageability of portage, or even because they think
> > Larry the Cow just owns.
>
> hehe. I totally agree. I choose Gentoo for the flexibility, for instance
> in getting the programversions I want to use - except I'm sad that
> gcc-versions get phased out too quickly IMHO, so I can't easily choose to
> stay with an "old" gcc like 3.2.2 - without running into packages I
> suddenly can't upgrade automatically, because they depend on a newer GCC,
> which I can see no reason for them to do.

Most applications should not explicitly depend on a specific version of the 
compiler. There are however some serious bugs in certain compiler versions 
that show up in certain complex applications (like openoffice). Those bugs 
are sometimes a reason to stop support for that particular version (although 
not using -march=pentium4 stops most 3.2.x family problems)
>
> You are probably right - especially when I'm told that gcc-3.5 has great
> profiling capabilities (GIMPLE - whatever that is :) - which I agree would
> be the better solution (so people can easily optimize their machine -
> doing profiles for their usage).

According to wikipedia and the gcc website it is an intermediate machine 
independent language that is used for optimization.

> The idea would ofcourse be that, only the "obvious" programs would be
> tested - but if profiling were implemented/possible with gcc-3.5 and
> portage easily - I'm  fairly certain that would be of more value (would
> that also help select the right CFLAGS ?)

Easy profiling mainly shows where bottlenecks are (not the subtle ones that 
involve the cpu cache for example, for that you might want to try the 
valgrind cachegrind module)

Paul

-- 
Paul de Vrieze
Gentoo Developer
Mail: pauldv@gentoo.org
Homepage: http://www.devrieze.net

[-- Attachment #2: Type: application/pgp-signature, Size: 189 bytes --]