harmony-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Steve Blackburn <Steve.Blackb...@anu.edu.au>
Subject Re: [arch] VM Candidate : JikesRVM http://jikesrvm.sourceforge.net/
Date Thu, 19 May 2005 08:44:41 GMT
acoliver@apache.org wrote:

> The problem of Java written JVM/JIT isn't one of performance.  You can 
> theoretically achieve the same performance (although I'm not 100% 
> convinced, I'm partially there) especially if you're willing to 
> "extend" Java for the purpose of writing Java.
> That being said...doing so in a portable and platform independent way 
> is actually HARDER in Java than in C (and by C I mean 
> C/C++/Objective-C...whatever).  Read the Sable paper...  you'll see 
> what I mean :-)

I don't see how it follows.  The Sable paper is a PhD thesis describing 
the design of Sable VM, which is written in C and is portable.  What 
does that say about the relative difficulty of doing it in Java?

Further, it is important to differentiate architectural portability from 
OS portability.

OS portability in a VM like Jikes RVM is very easy since there is a very 
well defined narrow interface to the OS, written in C.

Architectural portability is a different issue altogether.  If your VM 
has a JIT, then you will need a new back end (regardless of whether the 
JIT is written in C or Java).


View raw message