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From "Yuri Kashnikoff" <yuri.kashnik...@gmail.com>
Subject Re: [perf] Comparative benchmarking
Date Wed, 07 Nov 2007 16:34:09 GMT
> Yuri Kashnikoff did this patch and I hope we will commit it before M4.
> Yuri, can you share your patch with us?
Yes, Mikhail. LightJNI available by
https://issues.apache.org/jira/browse/HARMONY-5084.
All information about LightJNI provided(just use the link).

>
> On Nov 7, 2007 5:46 AM, Xiao-Feng Li <xiaofeng.li@gmail.com> wrote:
> >
> > On Nov 7, 2007 7:09 AM, Robin Garner <robin.garner@anu.edu.au> wrote:
> > >
> > > Aleksey Shipilev wrote:
> > > > On 07 Nov 2007 00:27:25 +0300, Egor Pasko <egor.pasko@gmail.com>
wrote:
> > > >
> > > >> Vladimir, guess what? :) I actually mixed several things
> > > >> altogether.
> > > >>
> > > > <giggly>(sigh) As usual, miracle does not happen :) I dreamed to
see
> > > > software sqrt() implementation that could be faster than hardware one.
> > > > </giggly>
> > > >
> > > >
> > > >> So, we are left with SSE asm that can be inlined by JIT and AFAI can
> > > >> see it is not as fast as HotSpot? Weird :)
> > > >>
> > > > No, for now we have just the intrinsic in native code, so we also have
> > > > overheads for JNI transition (and it is heavy!), parameter passing,
> > > > chains of calls, etc. I believe that sqrt() magic will lead that NBody
> > > > performance very close to RI.
> > > >
> > > > BTW, in my thought this benchmark is like the top of the iceberg
> > > > called "FP performance problems".
> > > >
> > > > Thanks,
> > > > Aleksey.
> > > >
> > > You might be interested to know that the JikesRVM implementation calls
> > > out to glibc via a fast syscall (we have an @SysCall annotation for
> > > native methods), and it is 1.5x slower than Sun 1.6 on a Core2/Linux for
> > > Tim's (non-strict) benchmark.  Maybe you can squeeze the overhead of
> > > intrinsic calls down a bit further ?
> >
> > I am also wondering why not to leverage the system support directly.
> > This solution is by default portable. :-)
> >
> > > cheers
> > >
> > > cheers
> >
> > >
> >
> >
> >
> > --
> > http://xiao-feng.blogspot.com
> >
>
>
>
> --
> Mikhail Fursov
>


-- 
Yuri S. Kashnikov
Novosibirsk State University, Russia
2 Pirogova street
630090, Novosibirsk-90
yuri.kashnikoff@gmail.com

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