Java Memory Management on HP-UX

page 92/8/2005

Kernel tunables

• Even though maxdsiz may be set to a large value, the actual

available heap space (DATA) might be much lower because the

memory mapped (mmap) segments that are mapped private,

STACK, TEXT (EXEC_MAGIC case), Java heap, Java threads,

etc. also share this address space.

• Similarly, even though maxtsiz might be a large value, it

consumes only as much physical/virtual memory as the

executable requires.

• On the contrary, maxssiz consumes as much virtual space as

the value it is set to. In other words , raising maxssiz may

cause user processes which use all (or nearly all) of the

previously available data area to fail allocation with the

[ENOMEM] error, even with maxdsiz set above the current

amount of memory allocated for data by this process.