UNIX Filesystems: Evolution, Design, and Implementation

Pre-SVR3 Kernels

With the exception of Lions' book on 6th Edition UNIX [LION96], no other UNIX kernels were documented in any detail until the arrival of System V Release 2 that was the basis for Bach's book The Design of the UNIX Operating System [BACH86]. In his book, Bach describes the on-disk layout to be almost identical to that of the earlier versions of UNIX.

There was little change between the research editions of UNIX and SVR2 to warrant describing the SVR2 filesystem architecture in detail. Around this time, most of the work on filesystem evolution was taking place at the University of Berkeley to produce the BSD Fast File System which would, in time, become UFS.