Does Java on Alpha Tru64 consume much more runtime memory than on Intel Windows?

[Geert Van Pamel]

I have an identical Java jar file running on both Alpha Tru64 and Windows Intel.

ps aux |head
USER PID %CPU %MEM VSZ RSS TTY S STARTED TIME COMMAND
apache 42048 0.0 14.8 161M 151M ?? S Mar 02 0:14.79 java -jar

We compare this to Windows 2003 Server running the same program

C:\> tasklist /fi "imagename eq java.exe"

Image Name PID Session Name Session# Mem Usage
java.exe 1672 Console 0 17.432 K

On Tru64 the program uses 150 MB virtual memory while on Windows it would only show 17 MB.

Would this indicate that Alpha Tru64 Java is using 9 x more memory than Windows??

The Windows machine is 32 bit, while the Alpha is 64 bit, so some data structures would consume more memory? Where is the difference? Or could it be an effect of the garbarge collector having a different behaviour?

Or did I understood that on Tru64 the Java opcode is compiled to native machine code? This could help to speed up the execution of the program at the expense of using more memory?