RE: Performance comparison of Java (and .NET) runtimes

["Boehm, Hans" <hans dot boehm at hp dot com>]

It would also be great to also get some qprof or oprofile profiles
for some of these, especially the gcj version.

(You can get qprof from http://www.hpl.hp.com/research/linux/qprof/ .
For best results with gcj, compile with -O2 -g, but you can usually
get some useful information without that.)

My impression is that generally open source VM developers invest less
time in tuning for standard benchmarks than commercial efforts do.
That is likely to affect overall performance, but it also means that
gcj is likely to look relatively worst on SPEC benchmarks.

Hans

> -----Original Message-----
> From: java-owner@gcc.gnu.org 
> [mailto:java-owner@gcc.gnu.org]On Behalf Of
> shudo@computer.org
> Sent: Tuesday, October 19, 2004 11:07 AM
> To: mckinlay@redhat.com
> Cc: java@gcc.gnu.org
> Subject: Re: Performance comparison of Java (and .NET) runtimes
> 
> 
> Hi Bryce,
> 
> > >  Performance Comparison of Java/.NET Runtimes (Oct 2004)
> > >  http://www.shudo.net/jit/perf/
> 
> > Cool, thanks for posting that. It would be good to 
> understand why GCJ
> > does so poorly on some of the SPEC JVM scores. Did you ever 
> try it with
> > -ffast-math and/or -march=pentium4? (also, perhaps 
> -fno-bounds-check,
> > but I guess that is cheating)
> 
> Now I tried those options and saw some amount of improvement.
> The score of _222_mpegaudio improved 15% and the total score 
> improved 4%.
> 
> [Only -O2]
> 
>   _227_mtrt       122
>   _202_jess       87.0
>   _201_compress   187
>   _209_db         29.0
>   _222_mpegaudio  375
>   _228_jack       56.1
>   _213_javac      103
> 
> [-O2 -march=pentium4 -ffast-math]
> 
>   _227_mtrt       125
>   _202_jess       90.0
>   _201_compress   190
>   _209_db         29.3
>   _222_mpegaudio  430
>   _228_jack       56.7
>   _213_javac      107
> 
> The version of the gcj I used is as follows:
> 
>   % gcj -v
>   ...
>   gcc version 3.4.2 20041017 (Red Hat 3.4.2-6)
> 
>   % rpm -q gcc-java
>   gcc-java-3.4.2-6
> 
> 
>   Kazuyuki Shudo	shudo@computer.org	http://www.shudo.net/
>