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-Matthew

On February 11, 2004 10:44 pm, Jeff Hubbs wrote:
> There's another reason why I ask.  I frequently install Gentoo on slow
> machines because a) I want to wring every last bit of performance I can
> out of the hardware available and b) I'm not under time pressure to do
> so :)
>
> But, according to this, in doing so and accepting the -O3 optimization
> suggested, I may only be hurting myself, ESPECIALLY if after building
> gcc, glibc, etc. in the bootstrap phase with -O3 and subsequently
> compiling everything else with that gcc, it might be taking m hours
> (days?) longer than necessary.
>
> I'd run tests. but I'd better do it on a CPU from this century or it'll
> take so long I'll forget what I'm testing.
>
> - Jeff
>
> On Wed, 2004-02-11 at 22:37, Jeff Hubbs wrote:
> > Can someone explain to me why the -O3 optimization would make programs
> > run *slower*?  In asking, I'm not trying to cast aspersions or challenge
> > the assertion, I'm really only just trying to ask how this is so.
> >
> > - Jeff
> >
> > On Wed, 2004-02-11 at 19:23, James Sumners wrote:
> > > Stupid exmh didn't send this with the correct From: address earlier
> > > today.
> > >
> > > >From the November 04, 2003 Debian news
> > >
&gt; &gt; &gt; (<a  rel="nofollow" href="http://lists.debian.org/debian-news/debian-news-2003/msg00056.html";>http://lists.debian.org/debian-news/debian-news-2003/msg00056.html</a>):
&gt; &gt; &gt;
&gt; &gt; &gt;  --- Begin Quote ---
&gt; &gt; &gt;  Debian faster than Gentoo? Matt Garman [2]wondered why his C++
&gt; &gt; &gt;  program ran dramatically slower when compiled on a Gentoo machine than
&gt; &gt; &gt;  when compiled with Debian Sid. He later [3]reported that recompiling
&gt; &gt; &gt;  the Gentoo C++ libraries with less aggressive optimization flags (-O2
&gt; &gt; &gt;  instead of -O3) eliminated the speed difference. Matt also [4]added
&gt; &gt; &gt;  that Debian and other distributions are conservative, but set up by
&gt; &gt; &gt;  very experienced people.
&gt; &gt; &gt;
&gt; &gt; &gt;   2. <a  rel="nofollow" href="http://article.gmane.org/gmane.linux.gentoo.user/50924";>http://article.gmane.org/gmane.linux.gentoo.user/50924</a>
&gt; &gt; &gt;   3. <a  rel="nofollow" href="http://article.gmane.org/gmane.linux.gentoo.user/50973";>http://article.gmane.org/gmane.linux.gentoo.user/50973</a>
&gt; &gt; &gt;   4. <a  rel="nofollow" href="http://article.gmane.org/gmane.linux.gentoo.user/50953";>http://article.gmane.org/gmane.linux.gentoo.user/50953</a>
&gt; &gt; &gt;  --- End Quote ---
&gt; &gt; &gt;
&gt; &gt; &gt;  Basically, Red Hat (Fedora) packages are typically compiled in a
&gt; &gt; &gt; haphazard fashion in relation to the other packages in the
&gt; &gt; &gt; distribution. The packages in Debian go through an arduous testing
&gt; &gt; &gt; process and are built according to rather strict rules.
&gt; &gt; &gt;
&gt; &gt; &gt; James Sumners
&gt; &gt; &gt;
&gt; &gt; &gt; On Wed, 11 Feb 2004 13:12:30 -0500
&gt; &gt; &gt;
&gt; &gt; &gt; Keith Morris - IQ &lt;keith at iqtv.com&gt; wrote:
&gt; &gt; &gt; &gt; Hi all, just wanted to share a quick experience and get your opinions
&gt; &gt; &gt; &gt; if you are willing.
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; I have been using linux off and on since Redhat 5.1 and exclusively
&gt; &gt; &gt; &gt; for the last 3 years at home.  I have pretty much been a redhat man
&gt; &gt; &gt; &gt; with no complaints.  I use Fedora Core 1 on my 2 main machines at
&gt; &gt; &gt; &gt; home (both 1.6GHz).  Well, recently I got a PIII 866 to play with and
&gt; &gt; &gt; &gt; installed FC1 on it and the speed was really quite sluggish.  Played
&gt; &gt; &gt; &gt; with a few more distros which I wasn't really happy with.  Well, I've
&gt; &gt; &gt; &gt; always been afraid of Debian with it's infamous hell-installer, but
&gt; &gt; &gt; &gt; with it's new Beta installer, I decided to try it.
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; After a pretty painless net-install, I was totally shocked with the
&gt; &gt; &gt; &gt; speed of Debian.  Easily twice as fast as Fedora on the 866 using the
&gt; &gt; &gt; &gt; *SAME* software (Gnome 2.4, KDE 3.1.5, OpenOffice, Evolution, XFT
&gt; &gt; &gt; &gt; support, antialiasing, etc.) I still have not gotten the sound
&gt; &gt; &gt; &gt; working, but believe that I will be able to (with a few posts to the
&gt; &gt; &gt; &gt; ALE list :)) The only main difference is that I formatted / with
&gt; &gt; &gt; &gt; reiserfs instead of ext3 with FC1.
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; I was wondering if anyone could guess why debian would be sooooo much
&gt; &gt; &gt; &gt; faster with basically the same &quot;Desktop&quot; type of configuration? Do
&gt; &gt; &gt; &gt; many of you use Debian?
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; I will probably stick with Debian on this machine to learn about the
&gt; &gt; &gt; &gt; different ins-and-outs.  I absolutely *love* apt-get for debian.  I
&gt; &gt; &gt; &gt; have used it with rpms on redhat, but it seems better with
&gt; &gt; &gt; &gt; debs...dunno...
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; Anyway, thanks for letting me share.
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; Keith Morris
&gt; &gt; &gt; &gt; Creative Director
&gt; &gt; &gt; &gt; Design / Effects
&gt; &gt; &gt; &gt; IQ television group
&gt; &gt; &gt; &gt; <a  rel="nofollow" href="http://www.iqtv.com";>http://www.iqtv.com</a>
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt;
&gt; &gt; &gt; &gt; _______________________________________________
&gt; &gt; &gt; &gt; Ale mailing list
&gt; &gt; &gt; &gt; Ale at ale.org
&gt; &gt; &gt; &gt; <a  rel="nofollow" href="http://www.ale.org/mailman/listinfo/ale";>http://www.ale.org/mailman/listinfo/ale</a>


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<li><strong><a name="00417" href="msg00417.html">-O3 vs. -O2 (was Re: [ale] sharing an experience....debian....)</a></strong>
<ul><li><em>From:</em> hbbs at comcast.net (Jeff Hubbs)</li></ul></li>
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<li><strong><a name="00388" href="msg00388.html">[ale] sharing an experience....debian....</a></strong>
<ul><li><em>From:</em> keith at iqtv.com (Keith Morris - IQ)</li></ul></li>
<li><strong><a name="00412" href="msg00412.html">-O3 vs. -O2 (was Re: [ale] sharing an experience....debian....)</a></strong>
<ul><li><em>From:</em> hbbs at comcast.net (Jeff Hubbs)</li></ul></li>
<li><strong><a name="00413" href="msg00413.html">-O3 vs. -O2 (was Re: [ale] sharing an experience....debian....)</a></strong>
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