Wikipedia
AdvFS
AdvFS, also known as Tru64 UNIX Advanced File System, is a file system developed in the late 1980s to mid-1990s by Digital Equipment Corporation for their OSF/1 version of the Unix operating system (later Digital UNIX/ Tru64 UNIX). In June 2008, it was released as free software under the GNU GPLv2 license. AdvFS has been used in high-availability systems where fast recovery from downtime is essential.