You can then also install the 64-bit JRE so standard apps (i.e. non applets and WebStart apps) run as 64-bit. If you do that, I'd recommend installing the 32-bit version of the JRE first, then the 64-bit. Or installing the 32-bit JRE and than the 64-bit JDK, installing the JRE along with it.
Hello, thanks for the very quick reply..
I did learned a lot from your post.
What I did was to install this version jdk-6u1-windows-i586-p.exe in the 64 bit windows xp machine. From what I have learned from your post, this is a 32 bit version.
My application seems to be running as expected, I just notice that in the Task Manager that the java exe runs as javaw.exe *32.
I have no applets or webstarts in my apps.
I just have one more query, if I will remain in my current setup (installed a 32 bit jre in a 64 bit os) will there be any problem or tradeoffs in my current apps? Or the best and efficient way is to download the 64 bit jre version and install it in my target desktop.
On a 64-bit capable jdk only the Java HotSpot Server VM is supported so the -server option is implicit. This is subject to change in a future release.
Starting with J2SE 5.0, when an application starts up, the launcher can attempt to detect whether the application is running on a "server-class" machine and, if so, use the Java HotSpot Server Virtual Machine (server VM) instead of the Java HotSpot Client Virtual Machine (client VM). The aim is to improve performance even if no one configures the VM to reflect the application it's running. In general, the server VM starts up more slowly than the client VM, but over time runs more quickly.
"...every native pointer in the system takes up 8 bytes instead of 4. The loading of this extra data has an impact on memory usage which translates to slightly slower execution depending on how many pointers get loaded during the execution of your Java program. ... On AMD64 and EM64T platforms this difference ranges from 0-15% [degradation] depending on the amount of pointer accessing your application performs. " (more detail in the answer to this question at the site)
One more thing, that keeps me thinking also is that I use SWT as my GUI toolkit instead of the standard SWING toolkit. I am not sure if there will be problems that I have not foreseen.
Also, I am thinking about what you have said that my app may not run as 64 bit since my jre is 32 bit. I may not be utilizing the full potential of my operating system. Any views on this, Thanks again.