max size of java -Xmx for aix5.3

[cnwy]

Hi,
p550,2 cpu,8G ram,Aix5.3
We could use 3g as the max heap size,but failed with 4g.
Any suggestions?
wy.

 

[Roedy Green]

We could use 3g as the max heap size,but failed with 4g.
Any suggestions?

IF you have a 32 bit machine, you have a 4GIG addressing limit. You
have to leave some room for the OS, code, DLLs etc.

Look into a 64-bit machine.
see
http://mindprod.com/bgloss/sixtyfourbit.html

that is not a type. bgloss is the hardware glossary.