If you select a ZFS root file system during an initial installation or use live upgrade to migrate from a UFS root file system to a ZFS root file system, a swap area is created on a ZFS volume in the ZFS root pool. The swap area size is based on 1/4 to 1/2 of physical memory.
# swap -l swapfile dev swaplo blocks free /dev/zvol/dsk/rpool/swap 253,3 16 8257520 8257520
A ZFS volume is also created for the dump device. Currently, the swap area and the dump device must reside on separate ZFS volumes.
If you need to modify your ZFS swap area after installation, then use the swap command as in previous Solaris releases. For more information, see Chapter 21, Configuring Additional Swap Space (Tasks), in System Administration Guide: Devices and File Systems.
For information about managing dump devices, see Managing System Crash Dump Information.