-Xiss / -Xss / -Xssi

Determines the size and behavior of the stack size for Java™ threads.

To increase the maximum number of threads your system can support, reduce the maximum native stack size.

If you exceed the maximum Java thread stack size, a java/lang/OutOfMemoryError message is reported.

You can use the -verbose:sizes option to find out the values that the VM is currently using.


Setting Effect Default
-Xiss<size> Set initial Java thread stack size 2 KB
-Xss<size> Set maximum Java thread stack size 320 KB (31/32-bit); 1024 KB (64-bit)
-Xssi<size> Set Java thread stack size increment 16 KB

See Using -X command-line options for more information about the <size> parameter.

See Default settings for the OpenJ9 VM for more about default values.

See also

  • -Xmso (Initial stack size for operating system threads)