Before you install the Solaris software, you can determine if your system has enough disk space by doing some high-level planning.

For each file system that you create, allocate an additional 30 percent more disk space than you need to enable you to upgrade to future Solaris versions.

By default, the Solaris installation methods create only root (/) and /swap. When space is allocated for OS services, the /export directory is also created. If you are upgrading to a major Solaris release, you might need to reslice your system or allocate double the space that you need at installation time. If you are upgrading to an update, you could prevent having to reslice your system by allocating extra disk space for future upgrades. A Solaris update release needs approximately 10 percent more disk space than the previous release. You can allocate an additional 30 percent of disk space for each file system to allow space for several Solaris updates.

If you intend to use the crash dump feature savecore(1M), allocate double the amount of your physical memory in the /var file system.

The Solaris installation program allocates a default swap area of 512 Mbytes under the following conditions:

  • If you use the installation program’s automatic layout of disk slices
  • If you avoid manually changing the size of the swap slice

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 based 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 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 an overview of the swap space, see Chapter 21, Configuring Additional Swap Space (Tasks), in System Administration Guide: Devices and File Systems.