Allocating Swap Space for UFS-Based Systems (System Administration Guide: Devices and File Systems)

System Administration Guide: Devices and File Systems

Allocating Swap Space for UFS-Based Systems

After you have assessed the swap requirements of your applications, use the following general guidelines to allocate swap space and dump device size for systems that run a UFS root file system.

System Type	Swap Space Size	Dedicated Dump Device Size
Workstation with about 4 Gbytes of physical memory	1 Gbyte	1 Gbyte
Mid-range server with about 8 Gbytes of physical memory	2 Gbytes	2 Gbytes
High-end server with about 16 to 128 Gbytes of physical memory	4 Gbytes	4 Gbytes

In addition to these general guidelines, consider allocating swap space or disk space for the following:

A dedicated dump device.
The /var/crash directory. The default system crash dump content is kernel memory pages only and the dump is compressed before it is written. Consider sizing this directory to the size of the dump device unless you attend to keep several system crash dumps.
Determine whether large applications (such as compilers) will be using the /tmp directory. Then, allocate additional swap space to be used by TMPFS. For information about TMPFS, see Swap Space and the TMPFS File System.