|Next: Networking, Release 2 Up: Twenty Years of Berkeley Previous: Networking, Release 1|
Meanwhile, development continued on the base system. The virtual memory system whose interface was first described in the 4.2BSD architecture document finally came to fruition. As was often the case with the CSRG, we always tried to find existing code to integrate rather than write something from scratch. So, rather than design a new virtual memory system, we looked around for existing alternatives. Our first choice was the virtual memory system that appeared in Sun Microsystem's SunOS. Although there was some discussion about Sun contributing the code to Berkeley, nothing came of those talks. So we went with our second choice, which was to incorporate the virtual memory system from the MACH operating system done at Carnegie-Mellon University. Mike Hibler at the University of Utah merged the core technology from MACH with the user interface described by the 4.2BSD architecture manual (which was also the interface used by SunOS).
The other major addition to the system at the time was a Sun-compatible version of the Network Filesystem (NFS). Again the CSRG was able to avoid writing the actual NFS code, instead getting an implementation done by Rick Macklem at the University of Geulph in Canada.
Although we did not yet have the complete feature set of 4.4BSD ready to ship, the CSRG decided to do an interim release to get additional feedback and experiences on the two major new additions to the system. This licensed interim release was called 4.3BSD-Reno and occurred in early 1990. The release was named after a big gambling city in Nevada as an oblique reminder to its recipients that running the interim release was a bit of a gamble.