Locus Computing Corporation was formed in 1982 by Gerald J. Popek, Charles S. Kline and Gregory I. Thiel to commercialize the technologies developed for the LOCUSdistributed operating system at UCLA. Locus was notable for commercializing single-system image software and producing the Merge package which allowed the use of DOS and Windows 3.1 software on Unix systems. Locus was acquired by Platinum Technology Inc in 1995.
Locus was commissioned by IBM to produce a version of the AIX UNIX based operating system for the PS/2 and System/370 ranges. The single-system image capabilities of LOCUS were incorporated under the name of AIX TCF.
Locus was commissioned by Intel to produce a multiprocessor version of OSF/1 for the Intel Paragon a massively parallelNORMA system. The system was known as OSF/1 AD, where AD stood for "Advanced Development". To allow inter processor process migration and communication between the individual nodes of the Paragon system they re-worked the TCF technology from LOCUS as Transparent Network Computing, or TNC, inventing the concept of the VPROC an analogy of the VNODE from the SunOSvirtual file system.
Locus was commissioned by Tandem Computers to include their TNC technology in a highly available single-system image clustering system based on SCO UnixWare, UnixWareNonStop Clusters. During the course of the project Locus was acquired by Platinum Technology Inc, who transferred the team working on NonStop Clusters to Tandem. Tandem were later bought by Compaq. The UnixWare product was acquired from SCO by Caldera Systems/Caldera International, who discontinued commercialization of the NonStop Clusters product in favor of the simpler Reliant HA system. Compaq then decided to release the NonStop Clusters code as open source software, porting it to Linux as the OpenSSI project.
Merge
was a system developed by Locus in late 1984 for the AT&T 6300+ computer, which allowed DOS to be run under the native UNIX SVR2 operating system. The 6300+ used an Intel 80286 processor and included special purpose circuitry to allow virtualization of the 8086 instruction set used by DOS. Merge was later modified to use the virtual 8086 mode provided by Intel 80386 processors. It was sold for MicroportSVR3 and later SCO Unix and UnixWare. In the late 1980, the main commercial competitor of Merge was VP/IX developed by Interactive Systems Corporation and Phoenix Technologies. Around 1994, Merge included an innovative socket api which used Intel ring 2 for virtualization. Although this was the fastest network access of any Windows virtualization system then on the market, it did not increase sales enough to make Locus independent. This socket api was designed and developed by Real Time, Inc. of Santa Barbara. Locus eventually joined the MicrosoftWISE program which gave them access to Windows source code, which allowed later versions of Merge to run Windows Shrink wrapped applications without a copy of Windows.
