Kaffe much slower than JDK

Eric S Fraga ucecesf at minerva.chemeng.ucl.ac.uk
Sun Nov 30 04:44:12 PST 1997

I hope somebody can help me: I used to use kaffe when I was developing
code using the 1.0.2 version of the JDK. Since I moved to 1.1.3, I
stopped using kaffe. Recently, however, I decided I would try kaffe
again (as I had been very impressed with it before).

I've downloaded 0.9.2 and installed it on my Linux box. Works very well
on the benchmarks and on a few small apps I've written to test it out
for myself.  However, when I try my major app, the performance with 
kaffe is horrendous. The JDK outperforms kaffe to the tune of at least
one order of magnitude (even though on all the small tests I've done,
kaffe comes out approximately 4 times faster than the JDK).

My application takes many minutes to hours of elapsed time so a potential
4 times increase in speed is very desirable. However, I can't seem to
figure out what is causing kaffe to perform so badly. 

Can anybody suggest any factors which could cause this behaviour? My
code is highly recursive with large numbers of different objects being
created and then discarded (simple tests indicate this shouldn't be
a problem per se). There is a great deal of string manipulation and also
a lot of floating point arithmetic.

Any suggestions etc more than welcome!

Eric S Fraga, Chem & Biochem Eng, UCL, www.chemeng.ucl.ac.uk/staff/fraga.html

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