Chapter 5 Guidelines for Allocating Disk Space and Swap Space (Planning)

This chapter describes general guidelines for planning the disk space that you need to install or upgrade the Solaris operating environment. It also describes default swap space allocation. This chapter contains the following sections:

• Allocating Disk Space

• SPARC: How Swap Space Is Allocated

Allocating Disk Space

Before you install the Solaris 9 software, you can determine if your system has enough disk space by doing some high-level planning. If you plan your disk space needs before you install, you can add more disks to your system, if you need them, before you install the Solaris 9 software. If you are upgrading, review Upgrading With Disk Space Reallocation.

General Disk Space Planning and Recommendations

Planning disk space is different for everyone. Consider the following general points when you are planning disk space:

• Allocate additional disk space for each language you select to install, for example, Chinese, Japanese, Korean.

• If you intend to support printing or mail, allocate additional disk space in the /var file system.

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

• If a server provides home directory file systems for users on other systems, allocate additional disk space on the server. By default, home directories are usually located in the /export file system.

• Allocate at least 512 Mbytes of swap space.

• Allocate space for the Solaris software group you want to install. The recommended disk space for the software groups is in Table 5–1. When you are planning disk space, remember that you can add or remove individual software packages from the software group that you select.

• Create a minimum number of file systems. By default, the Solaris installation methods create only root (/) and /swap. When space is allocated for OS services, the /export directory is also created. 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. Each new Solaris release needs approximately 10 percent more disk space than the previous release. By allocating an additional 30 percent of disk space for each file system, you allow for several Solaris upgrades before you need to reslice your system.

• Allocate additional disk space for additional software or third-party software.

If you are using Solaris Live Upgrade, see Solaris Live Upgrade Disk Space Requirements.

Disk Space Recommendations for Software Groups

The Solaris software groups are collections of Solaris packages. Each software group includes support for different functions and hardware drivers. You select the software group to install, based on the functions that you want to perform on the system.

• Core System Support Software Group — Contains the minimum code that is required to boot and run a networked Solaris system.

• End User Solaris Software Group – Contains the minimum code that is required to boot and run a networked Solaris system and the Common Desktop Environment.

• Developer Solaris Software Group – Contains the End User Software Group plus additional support for software development. The additional software development support includes libraries, include files, man pages, and programming tools. Compilers are not included.

• Entire Solaris Software Group – Contains the Developer Solaris Software Group and additional software that is needed for servers.

• Entire Solaris Software Group Plus OEM Support – Contains the Entire Solaris Software Group plus additional hardware drivers, including drivers for hardware that is not on the system at the time of installation.

When you are installing the Solaris software, you can choose to add or remove packages from the Solaris software group that you selected. When you are selecting which packages to add or remove, you need to know about software dependencies and how the Solaris software is packaged.

The following table lists the Solaris software groups and the recommended amount of disk space that you need to install each group.

Swap space is included in the disk space recommendations.

SPARC: How Swap Space Is Allocated

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.