[Cooker] Fwd: mpeg2enc timing results [narfi@cs.wisc.edu]

[Austin]

Here's a simple benchmark from Narfi.

Athlon XP 2100.
Asus A7N8X motherboard (NForce2)
512 MB memory, PC2700 2-2-2
Mandrake 9.0
###############
# Compiling for athlon-xp
export CFLAGS="-march=athlon-xp -mcpu=athlon-xp -O3 -finline-limit=10000
-ffast-math -fomit-frame-pointer"; export CXXFLAGS=$CFLAGS; make clean;
./configure  --disable-assert --enable-cmov-extension --enable-simd-accel;
make
###############
# Compiling for i586
export CFLAGS="-march=i586 -mcpu=i586 -O3"; export CXXFLAGS=$CFLAGS; make
clean; ./configure  --disable-assert --enable-cmov-extension
--enable-simd-accel; make
###############
# Compiling for i586, no MMX used
export CFLAGS="-march=i586 -mcpu=i586 -O3"; export CXXFLAGS=$CFLAGS; make
clean; ./configure  --disable-assert --disable-cmov-extension
--disable-simd-accel; make
He ran these 3 versions of mpeg2enc one after the other, each 3
times and I picked the best time for each version. The file encoded was
only 127MB so it fit into RAM.
The best times of the 4 were:
athlon-xp:    12.16
i586:         13.24
i586, no mmx: 57.65
[ start quote ]

In short: There are >>some<< packages which >>need to<< have mmx enabled.
These numbers should show that beyond any doubt!
How we do it is a different question.

My opinion is that going all the way and allowing the user to recompile all
packages is a potential support nightmare that Mandrake cannot risk and that
we should do the minimal: Only do this for a small number of select packages
where one can prove there is a significant benefit.
If somebody recompiles OOo for athlon-xp and can show that the startup time
after a reboot can be cut by 50% when compared to the i586 version, I am all
for it. Otherwise, I don't think it's worth the risk.
Narfi

[ end quote ]

So you see,  4.4 times faster by enabling MMX, and 4.7 times faster by also 
enabling fast-math athlon XP.  Thus it looks like your average app will see 
very little increase in performance by recompiling for XP or P4 or whatever, 
but as it stands now, our video apps are almost unuseably slow.

Austin