mixed mode execution

[Naresh Agarwal]

Hi

What is the "mixed mode" execution in java? What are other modes of execution?

thanks,
Naresh

 

[Michael Borgwardt]

What is the "mixed mode" execution in java? What are other modes of execution?

The modes of execution are "compiled" and "interpreted". Modern JVMs mix both by
selectively compiling to machine code only those parts of the bytecode that are
executed most often (and applying special runtime optimizations). This avoids the
compilation overhead for those parts of the code where it would yield no benefits.

 

[Naresh Agarwal]

thanks for reply Micheal.

Current Sun JVMs use HotSpot technology, which itself means "mixed"
mode.

Is it possible to use HotSpot VM in conjuction with "compiled" or
"interpreted" mode?

thanks,
Naresh

 

[Michael Borgwardt]

thanks for reply Micheal.

Current Sun JVMs use HotSpot technology, which itself means "mixed"
mode.

Is it possible to use HotSpot VM in conjuction with "compiled" or
"interpreted" mode?

Look at the docs for the java tool. It has an -Xint option to disable JIT
compilation, forcing it into pure interpreted mode. I'm not sure if it's
possible to force it to compile everything: the -Xbatch option prevents
the interpreted execution of methodes that are being compiled, but that
doesn't necessarily mean all methods are compiled.