Sun has already announced that it will fully support 64-bit processors very rapidly, as well as dual-cores.
All this should come starting next summer, with the release of Windows x64, and the start of Longhorn in next August.
The issues are not in Limewire, but in the OS kernels, and in the compiler supports for the new OSes, and more importantly in the support of security within OS and applications.
This requires collaboration between OS vendors (Microsoft, Sun, IBM, RedHat, ...), CPU manufacturers (Intel, AMD, IBM) for updates in the kernel drivers and compiler optimizers, and Java VM vendors (mostly Sun, BEA, Oracle and BEA).
So Limewire will run mostly without change on future 64-bit Java platforms. For now, there's simply no stable platform to deploy it.
There are products already available now, but they are only for tests, and they badly interroperate for now.
Limewire should only depend on Java VM support for 64-bit architectures. Until then, Java 1.5 already uses the 64-bit wide registers for internal operations that benefit from them (notably long integers, and Java2D), but the core program is still using 32-bit pointers.
Even when OSes will be 64-bit, very few people will benefit of a 64-bit addressing space, because 32-bit is ample enough to support the memory needed by an application including its swapped area. 64-bit is really important mostly for servers that need to address very large databases.
I'm not sure that upgrading to 64-bit will be significantly faster (for now the native 64-bit mode is in fact... slower than 32-bit emulation mode with WoW). And it takes more resources on the system (so you need 64-bit processors with larger but expensive internal caches, and more memory).
It seems that the dual-core architectures (including HyperThreading) will be more useful immediately. |