A new TMPFS-mounted file system, /var/run, is the repository for temporary system files that are not needed across system reboots in this Solaris release and future releases. The /tmp directory continues to be repository for non-system temporary files.
Because /var/run is mounted as a memory-based file system rather than a disk-based file system, updates to this directory do not cause unnecessary disk traffic that would interfere with systems running power management software.
The /var/run directory requires no administration. You may notice that it is not unmounted with the umount -a or the umountall command.
For security reasons, /var/run is owned by root.