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Re: [tlug] CentOS to Gentoo-Pros/Cons(if any)?



>>>>> "Josh" == Josh Glover <jmglov@example.com> writes:

    Josh> Remember, all of my professional systems programming was
    Josh> done for a telecom services company, where we were more than
    Josh> happy to trade size (both on disk and in memory) for
    Josh> execution speed every time. Working with real-time and
    Josh> time-sensitive telephone protocols will do that to you. :)

But my main point is that for a system like XEmacs (substitute Python,
Perl, Java, Ruby, VM-based-interpreter-du-jour) smaller _is_ faster.
See comment at line 1342 of xemacs/src/bytecode.c.  But I can also say
that whenever people do optimization tests on XEmacs, -Os is the only
thing that gives measurable speed up (~2%) over -O2 or -O3.[1]

I guess if you're the bad old AT&T you can afford custom-built CPUs
with quadruple-size on-chip cache, but really, is that any way to run
a stock exchange?



Footnotes: 
[1]  You will also find places (in src/buffer.c) where code
duplication and C-level loop unrolling is rampant.  This also gives
measured speed up, but it's carefully targeted, deliberate
optimization.



-- 
School of Systems and Information Engineering http://turnbull.sk.tsukuba.ac.jp
University of Tsukuba                    Tennodai 1-1-1 Tsukuba 305-8573 JAPAN
               Ask not how you can "do" free software business;
              ask what your business can "do for" free software.


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