In addition to preceding general guidelines, consider allocating swap space or disk space for a UFS-based system 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.