For most applications I would agree. GC is a pretty good way to go, it has a number of good properties such as fast allocation, pretty decent object grouping in many cases, pretty fast, etc.

However, you still can't work with raw memory, e.g. allocating blocks of memory for working with many of the same objects, moving objects around in physical memory, physically changing vtables for exisiting Java Objects (potentially useful for some optimizations). A JVM has more to do than just turn bytecode into native code, it also needs to manage memory, changing already JITed machine code, potentially changing existing object layouts/vtables.


--Will

çåç wrote:

Sure. So I think the new JVM should provide more good memory control than Hotspot. I think the escape analysis would help this.

So:
1. allocate object is mostly as quick as stack object. 2. most object will be gabage and throw away as quickly and takes no more GC cost.


In this case, we may inprove the memory control and makes the JVM more effective on GC.

:) it looks the Hotspot team dont believe escape analysis would help GC on the forums.java.net <http://forums.java.net> discussion.

2005/5/11, Will Pugh <[EMAIL PROTECTED]>:


I think you would also want to pay attention to how much control you
need over memory allocation. Java doesn't give you much control over
memory, yet in many scenarios (such as start-up time or running on
devices) working set can be just as important as the actual codes
executed for performance. You would have much more control over working
set/memory if you used C/C++.








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