I was running into the outofmemory errors on 32 bit IA32-linux machines. I read another posting on this forum about how running a similar program on AMD-64 seemed to resolve the issue, so I decided to run my program on an itanium.
I am using the sun jvm with the -Xms and -Xmx options, and the processor has enough RAM (8GB) and runs Debian linux, though i dont get errors like: 'cannot allocate enough heap' or the 'outOfMemory' errors, my program seems to freeze after a while. My program is very memory intensive and I would definitely expect it to do quite a bit of paging. My question is:
a. if the program needs more than the upper size does it use virtual memory, using paging mechanisms?
b. the upper limit i set is much higher than the physical RAM, though the system doesnt complain about this, is this a right thing to do. should i just set the upper limit to around 80% of physical RAM (recommended by SUN) and expect the system to trigger paging when it runs out of it.