[java] Could not reserve enough space for object heap to start JVM

Just faced with strange issue. When i type

java -version

i got

Error occurred during initialization of VM
Could not reserve enough space for object heap
Could not create the Java virtual machine.

.

java -Xms64m -Xmx64m -version

This command works fine

java version "1.6.0_24"
Java(TM) SE Runtime Environment (build 1.6.0_24-b07)
Java HotSpot(TM) Client VM (build 19.1-b02, mixed mode)

If i change xms, xmx to 128m, i get error again.

Using top command and free -m i can see, that i got over 192 mb free, so why i still get this error ?

Mem:    262144k total,    64760k used,   197384k free,        0k buffers
Swap:        0k total,        0k used,        0k free,        0k cached

Thank you

According to this post this error message means:

Heap size is larger than your computer's physical memory.

Edit: Heap is not the only memory that is reserved, I suppose. At least there are other JVM settings like PermGenSpace that ask for the memory. With heap size 128M and a PermGenSpace of 64M you already fill the space available.

Why not downsize other memory settings to free up space for the heap?

I had the same problem when using a 32 bit version of java in a 64 bit environment. When using 64 java in a 64 OS it was ok.