Q. I am running out of swap space due to Oracle database. This is a production server. How do I add a new swap file or area that doesn’t demand a reboot of the system?

A. Sun Solaris UNIX offers very easy way to add swap file or space on fly without rebooting Solaris system.

Login as the root user

Type the following command to create swap file. It creates file that are suitable for use as NFS- mounted swap areas.
# mkfile -v 2g tmp-swap.file

Where,
-v : Report the names and sizes of created files (verbose)
2g : 2Gbyte file size.

Now turn on or add the new swap file to the Solaris UNIX swap area:
# swap -a tmp-swap.file

The swap command provides a method of adding, deleting, and monitoring the system swap areas used by the memory manager.

This will do the job. Please note that this swap file is slow as compare to your regular raw swap device.

For more information refer to man pages of swap and mkfile command.