Locus Computing Corporation was formed in 1982 by

Gerald J. Popek Gerald John "Jerry" Popek (September 22, 1946 – July 20, 2008) was an American computer scientist, known for his research on operating systems and virtualization. With Robert P. Goldberg he proposed the Popek and Goldberg virtualization require ...

Charles S. Kline Charles is a masculine given name predominantly found in English and French speaking countries. It is from the French form ''Charles'' of the Proto-Germanic name (in runic alphabet) or ''*karilaz'' (in Latin alphabet), whose meaning was ...

and Gregory I. Thiel to commercialize the technologies developed for the

LOCUS Locus (plural loci) is Latin for "place". It may refer to: Entertainment * Locus (comics), a Marvel Comics mutant villainess, a member of the Mutant Liberation Front * ''Locus'' (magazine), science fiction and fantasy magazine ** ''Locus Award ...

distributed Distribution may refer to: Mathematics *Distribution (mathematics), generalized functions used to formulate solutions of partial differential equations *Probability distribution, the probability of a particular value or value range of a varia ...

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

UCLA The University of California, Los Angeles (UCLA) is a public university, public Land-grant university, land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a Normal school, teachers colle ...

. Locus was notable for commercializing

single-system image In distributed computing, a single system image (SSI) cluster is a cluster of machines that appears to be one single system. The concept is often considered synonymous with that of a distributed operating system, but a single image may be presente ...

software and producing the

Merge Merge, merging, or merger may refer to: Concepts * Merge (traffic), the reduction of the number of lanes on a road * Merge (linguistics), a basic syntactic operation in generative syntax in the Minimalist Program * Merger (politics), the com ...

package which allowed the use of DOS and

Windows 3.1 Windows 3.1 is a major release of Microsoft Windows. It was released to manufacturing on April 6, 1992, as a successor to Windows 3.0. Like its predecessors, the Windows 3.1 series ran as a shell on top of MS-DOS. Codenamed Janus, Window ...

software on

Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

systems. Locus was acquired by Platinum Technology Inc in 1995.

Products

AIX for IBM PS/2 and System/370

Locus was commissioned by IBM to produce a version of the AIX

UNIX Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

based operating system for the PS/2 and

System/370 The IBM System/370 (S/370) is a model range of IBM mainframe computers announced on June 30, 1970, as the successors to the System/360 family. The series mostly maintains backward compatibility with the S/360, allowing an easy migration path f ...

ranges. The

capabilities of

were incorporated under the name of AIX TCF (transparent computing facility).

OSF/1 AD for the Intel Paragon

Locus was commissioned by

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the devel ...

to produce a multiprocessor version of

OSF/1 OSF/1 is a variant of the Unix operating system developed by the Open Software Foundation during the late 1980s and early 1990s. OSF/1 is one of the first operating systems to have used the Mach kernel developed at Carnegie Mellon University, an ...

for the

Intel Paragon The Intel Paragon is a discontinued series of massively parallel supercomputers that was produced by Intel in the 1990s. The Paragon XP/S is a productized version of the experimental ''Touchstone Delta'' system that was built at Caltech, launc ...

massively parallel Massively parallel is the term for using a large number of computer processors (or separate computers) to simultaneously perform a set of coordinated computations in parallel. GPUs are massively parallel architecture with tens of thousands of t ...

NORMA Norma may refer to: * Norma (given name), a given name (including a list of people with the name) Astronomy * Norma (constellation) *555 Norma, a minor asteroid * Cygnus Arm or Norma Arm, a spiral arm in the Milky Way galaxy Geography *Norma, Laz ...

(No Remote Memory Access) 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

as Transparent Network Computing, or TNC, inventing the concept of the VPROC (virtual process) an analogy of the VNODE (virtual inode) from the

SunOS SunOS is a Unix-branded operating system developed by Sun Microsystems for their workstation and server computer systems. The ''SunOS'' name is usually only used to refer to versions 1.0 to 4.1.4, which were based on BSD, while versions 5.0 ...

virtual file system A virtual file system (VFS) or virtual filesystem switch is an abstract layer on top of a more concrete file system. The purpose of a VFS is to allow client applications to access different types of concrete file systems in a uniform way. A VFS ...

UnixWare NonStop Clusters

Locus was commissioned by

Tandem Computers Tandem Computers, Inc. was the dominant manufacturer of fault-tolerant computer systems for ATM networks, banks, stock exchanges, telephone switching centers, and other similar commercial transaction processing applications requiring maximum upt ...

to include their TNC technology in a highly available

clustering system based on SCO UnixWare, UnixWare NonStop 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 Compaq Computer Corporation (sometimes abbreviated to CQ prior to a 2007 rebranding) was an American information technology company founded in 1982 that developed, sold, and supported computers and related products and services. Compaq produced ...

. The UnixWare product was acquired from SCO by

Caldera Systems Caldera International, Inc., earlier Caldera Systems, was an American software company that existed from 1998 to 2002 and developed and sold Linux- and Unix-based operating system products. Caldera Systems was created in August 1998 as a spinoff ...

Caldera International Caldera International, Inc., earlier Caldera Systems, was an American software company that existed from 1998 to 2002 and developed and sold Linux- and Unix-based operating system products. Caldera Systems was created in August 1998 as a spinoff ...

, 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 Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Op ...

, porting it to

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which i ...

as the OpenSSI project.

Merge

was a system developed by Locus in late 1984 for the AT&T 6300+ computer, which allowed DOS (and hence DOS applications) to be run under the native

SVR2 Unix System V (pronounced: "System Five") is one of the first commercial versions of the Unix operating system. It was originally developed by AT&T and first released in 1983. Four major versions of System V were released, numbered 1, 2, 3, ...

operating system. The 6300+ used an Intel 80286 processor and included special-purpose circuitry to allow

virtualization In computing, virtualization or virtualisation (sometimes abbreviated v12n, a numeronym) is the act of creating a virtual (rather than actual) version of something at the same abstraction level, including virtual computer hardware platforms, st ...

of the 8086 instruction set used by DOS. Merge was later modified to use the

virtual 8086 mode In the 80386 microprocessor and later, virtual 8086 mode (also called virtual real mode, V86-mode, or VM86) allows the execution of real mode applications that are incapable of running directly in protected mode while the processor is running ...

provided by

Intel 80386 The Intel 386, originally released as 80386 and later renamed i386, is a 32-bit microprocessor introduced in 1985. The first versions had 275,000 transistorsMicroport SVR3 and later

SCO Unix Xinuos OpenServer, previously SCO UNIX and SCO Open Desktop (SCO ODT), is a closed source computer operating system developed by Santa Cruz Operation (SCO), later acquired by SCO Group, and now owned by Xinuos. Early versions of OpenServer we ...

and UnixWare. In the late 1980, the main commercial competitor of Merge was VP/IX developed by

Interactive Systems Corporation Interactive Systems Corporation (styled INTERACTIVE Systems Corporation, abbreviated ISC) was a US-based software company and the first vendor of the Unix operating system outside AT&T, operating from Santa Monica, California. It was founded in 1 ...

and

Phoenix Technologies Phoenix Technologies Ltd is an American company that designs, develops and supports core system software for personal computers and other computing devices. The company's products commonly referred to as BIOS (Basic Input/Output System) or fir ...

. Around 1994, Merge included an innovative socket API that 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

Microsoft Microsoft Corporation is an American multinational corporation, multinational technology company, technology corporation producing Software, computer software, consumer electronics, personal computers, and related services headquartered at th ...

WISE WISE may refer to: Arts, entertainment, and media * WISE (AM), a radio station licensed to Asheville, North Carolina *WISE-FM, a radio station licensed to Wise, Virginia * WISE-TV, a television station licensed to Fort Wayne, Indiana Education * ...

program which gave them access to

Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for ...

source code, which allowed later versions of Merge to run Windows ''Shrink wrapped'' applications without a copy of Windows.

PC-Interface

PC-Interface was a popular Lan-based Cross-Platform Integration Toolkit for Unix, providing MS-DOS/Windows/Macintosh and Unix integration using Unix as the file system. It supported AIX, Santa Cruz Operation Inc, UnixWare and Motorola 9000 and many other Unixes and came with one Mac and one MS-DOS/Windows client.

References

{{Reflist Defunct computer companies based in California Technology companies based in Greater Los Angeles Companies based in Los Angeles County, California Software companies established in 1982 Software companies disestablished in 1995 1982 establishments in California 1995 disestablishments in California Defunct software companies of the United States Defunct companies based in Greater Los Angeles 1995 mergers and acquisitions