Just some numbers that I got with a small testsuite.  This
is the setiathome client running on an AMD Athlon-500 (K7),
FreeBSD 4.0-current (as of 1999-09-18).  Of course, I've
used the same work unit for all tests.  I also changed the
code to stop after a certain amount of data has processed,
because I don't want to wait some hours for each test to
complete.  ;-)

-O1           302.72 real       301.96 user         0.28 sys
-O2           315.20 real       314.42 user         0.18 sys
-O3           320.01 real       319.23 user         0.35 sys
-Os           315.99 real       315.19 user         0.35 sys

As you can see, -O1 is fastest, the higher optimization levels
are slower.  I'm currently running a testsuite with a larger
number of optimizer flags combinations, but it'll take a while.

On a side note, I downloaded AMD's document about optimizing
code for the Athlon, and I found out that gcc does a pretty
poor job.  :-(  Unfortunately, I'm not an expert in writing
compilers, and I don't dare to touch the gcc source code.
After all, the compiler is one of the most critical parts of
the system.


Oliver Fromme, Leibnizstr. 18/61, 38678 Clausthal, Germany
(Info: finger userinfo:[EMAIL PROTECTED])

"In jedem Stück Kohle wartet ein Diamant auf seine Geburt"
                                         (Terry Pratchett)

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