Java performance on AMD64

[Greg Lewis]

On Fri, Apr 20, 2007 at 03:09:34AM -0400, Kris Kennaway wrote:
> On Fri, Apr 20, 2007 at 04:59:12PM +1000, Michael Vince wrote:
> > Kris Kennaway wrote:
> > >On Thu, Apr 19, 2007 at 12:32:53PM +1000, Michael Vince wrote:
> > >  
> > >>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.
> > >>    
> > >
> > >That's contrary to my benchmarks :( Dunno what might be wrong though,
> > >assuming you have checked all the obvious.
> > >
> > >Kris
> > >  
> > OK,
> > I did more testing and it appears the 6.1R Diablo Java binary package on 
> > Amd64 on 6.2/libthr appears to be the problem, it's as much as 60% 
> > slower then libpthread.
> > 
> > On 6.2R Amd64 I built the ports version of jdk1.5 and libthr appeared to 
> > be around 25% faster then libpthread.
> > But using the Diablo jdk package for 6.1R on 6.2 under libpthread is 
> > even faster by around 15% over anything I could do for any combination 
> > of Java and libthr.
> > 
> > I would guess that a new 6.2R Amd64 Diablo package would probably turn 
> > it around again for libthr and I would guess it would again around 20% 
> > faster then anything I can get from Java under AMD64 6.2R, what's going 
> > on here exactly I don't know.
> 
> That's weird, I thought the diablo package was just compiled from
> jdk1.5.  It could be there was a performance regression from a change
> made to the port after 6.1 - it would be great if you can follow it up
> with the java@ people.

Diablo is compiled from the partner source.  jdk15 is built on the SCSL
release.  The SCSL release was done when 1.5.0 was released.  The current
release of Diablo is based off of 1.5.0_07, so there were changes in between
the two that may/will affect performance.

-- 
Greg Lewis                          Email   : glewis at eyesbeyond.com
Eyes Beyond                         Web     : http://www.eyesbeyond.com
Information Technology              FreeBSD : glewis at FreeBSD.org