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java -Xms 512m

eric sato
Ranch Hand

Joined: Oct 01, 2002
Posts: 37
hi all,
This is short and simple question,to set maximum Java heap size in JVM, actually it draws memmory from RAM or Hardisk or both? pls advice. It this question dependency on OS level?
I'm running on Unix OS.
Thanks in advance.

If you can't change the direction the the wind, change your sail.
Peter den Haan
Ranch Hand

Joined: Apr 20, 2000
Posts: 3252
Java allocates its heap from memory. But any modern operating system will virtualise memory, i.e. use the harddisk to simulate more memory than you actually have. Application programs such as Java are not aware at all whether the memory they think they have is actually physical RAM or virtual memory on disk. And the OS will manage this dynamically anyway, so the situation can change from moment to moment.
- Peter
I agree. Here's the link:
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