Java performance on AMD64

[Michael Vince]

Hey All,
I been benchmarking Diablo Java under AMD64 on 6.2R and using the same 
methods I posted a while ago detailed somewhat here
http://lists.freebsd.org/pipermail/freebsd-java/2006-August/005576.html

The difference here is that libthr now works under Amd64.
But it appears libthr to be about half the speed of libpthread under 
AMD64 mode which is the opposite behavior when using it under i386.
The only other difference is that I am now using a 4 core server (total) 
Intel Core2 cpus, I tried testing under a dual core (total) server and 
the performance was just about exactly neck and neck between libpthread 
and libthr which is also somewhat wierd.
The servers are under stock 6.2R and I did have a multi IP jail patch 
applied and I tried removing that and it had no difference on performance.

Does any one know with there is such a large amount of difference of 
behavior between i386 and Amd64 on Java?

Thanks,
Mike