By default, the Solaris installation programs allocate swap space by placing swap so that it starts at the first available disk cylinder (typically cylinder 0 on SPARC systems.) This placement provides maximum space for the root (/) file system during the default disk layout and enables the growth of the root (/) file system during an upgrade. If you use the installation program's automatic layout of disk slices and avoid manually changing the size of the swap slice, the Solaris installation program allocates a default swap area of 512 Mbytes.
If you think you might need to expand the swap area in the future, you can place the swap slice so that it starts at another disk cylinder by using one of the following methods.
For the Solaris Web Start and Solaris suninstall programs, you can customize the disk layout in cylinder mode and manually assign the swap slice to the desired location.
For the Solaris custom JumpStart installation program, you can assign the swap slice in the profile file. For more information on the Solaris Custom JumpStart profile file, see Creating a Profile.
For an overview of the swap space, see “Configuring Additional Swap Space (Tasks)” in System Administration Guide: Basic Administration.