Re: [Qemu-devel] yet another proposed solution for gcc 4.x

[Carlo Marcelo Arenas Belon]

On Mon, Jun 05, 2006 at 01:21:48PM +0200, Christian MICHON wrote:
> did you get better benchmark results than using gcc-3.x ?

proportionally to native execution, yes (the gcc-4.1.1's compiled sha1-i386 
binary from the tests was slower than the one compiled with gcc-3.4.5)

results for running in an amd64 box with native x86 support and no kqemu for a
manually tweaked (as the Makefile won't work for amd64) `make speed` shown 
below :

for the gcc-3.4.5 compiled qemu 0.8.1 (vanilla untar in /var/tmp):

address@hidden /var/tmp/qemu-0.8.1/tests $ cat ../config-host.mak | grep CC
CC=gcc-3.4.5
HAVE_GCC3_OPTIONS=yes
HOST_CC=gcc-3.4.5

address@hidden /var/tmp/qemu-0.8.1/tests $ gcc-3.4.5 -m32 -Wall -O2 -g -o
sha1-i386 sha1.c 

address@hidden /var/tmp/qemu-0.8.1/tests $ time ./sha1-i386 
SHA1=15dd99a1991e0b3826fede3deffc1feba42278e6

real    0m0.027s
user    0m0.025s
sys     0m0.001s

address@hidden /var/tmp/qemu-0.8.1/tests $ time ../i386-user/qemu-i386
./sha1-i386 
SHA1=15dd99a1991e0b3826fede3deffc1feba42278e6

real    0m0.255s
user    0m0.250s
sys     0m0.005s

address@hidden /var/tmp/qemu-0.8.1/tests $ echo | awk '{ print 255/27; }'
9.44444

for the patched qemu with hybrid compilers (patched in /var/tmp with
directory name qemu-0.8.1-hybrid)

address@hidden /var/tmp/qemu-0.8.1-hybrid/tests $ cat ../config-host.mak |
grep CC
CC=gcc
HAVE_GCC3_OPTIONS=yes
HOST_CC=gcc
OP_CC=gcc-3.4.5

address@hidden /var/tmp/qemu-0.8.1-hybrid/tests $ gcc -m32 -Wall -O2 -g -o
sha1-i386 sha1.c

address@hidden /var/tmp/qemu-0.8.1-hybrid/tests $ time ./sha1-i386 
SHA1=15dd99a1991e0b3826fede3deffc1feba42278e6

real    0m0.031s
user    0m0.030s
sys     0m0.000s

address@hidden /var/tmp/qemu-0.8.1-hybrid/tests $ time ../i386-user/qemu-i386
./sha1-i386 
SHA1=15dd99a1991e0b3826fede3deffc1feba42278e6

real    0m0.287s
user    0m0.284s
sys     0m0.004s

address@hidden /var/tmp/qemu-0.8.1-hybrid/tests $ echo | awk '{ print 287/31;
}'
9.25806

Carlo

PS. is there any "standard" way to benchmark qemu that is all agreed upon as
authoritative other than `make speed`?
PS2. showing here the output of a typical sample, but obviously i run them
several times to eliminate any statistical noise.