JDK build questions

[David Dabbs]

> Subject: Re: JDK build questions
> 
> On Fri, Apr 16, 2010 at 10:24, David Dabbs wrote:
> >
> > On the premise that building my own binaries could yield performance
> > improvements versus the Sun(Oracle)-provided binaries I've decided to
> > tinker with building from source.
> >
> > * My first question is "Is this a reasonable premise?"
> 
> Unlikely, since the code that really counts is generated
> by the JIT at runtime.  The most performance-sensitive
> native code is probably the GC.
>

Since GC performance is important to me there may still be 
some relevance, I suppose.
 
> > * If so, is it possible to build using Intel's compiler?
> 
> You'll probably need to port, and to modify
> some underlying assumptions.
> I don't recommend it.
>

I'm not sure I understand your reference to "port." The Intel 
compiler is available on both Windows as well as Linux.
 
> > * Now that Visual Studio 2010 has been released will there be an
> >  option to use it to build the JDK under Windows?
> >
> > * If I build on a recent Xeon with "gcc -march=native ..." would one
> expect
> >  to see performance differences versus the Sun(Oracle)-provided
> binary to
> >  justify the effort?
> >
> > * I have recently been tinkering with Intel's memory allocator and
> TCMalloc,
> > etc.
> >  Would compiling with these be expected to a) even work and b) yield
> perf
> >  improvements worth the effort.
> 
> The JDK doesn't malloc much.
>

Perhaps my wording was inaccurate. The JDK may not malloc much, but if 
memory serves, the runtime uses a TLAB mechanism that might be enhanced 
for Intel multi-core by, say, Intel's TBB's "scalable allocator".
http://www.intel.com/technology/itj/2007/v11i4/5-foundations/5-memory.htm


> I would welcome having more choice of compilers,
> but I think it's a bigger project than it looks.
> 
> The IcedTea project has a "configure" infrastructure,
> that would be more accommodating to your goals.
> 
> Martin

Thank you for the pointer. I will look into IcedTea.

Best,

David