MkLinux (for Microkernel Linux) is an

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 ...

computer

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...

begun by the

Open Software Foundation The Open Software Foundation (OSF) was a not-for-profit industry consortium for creating an open standard for an implementation of the operating system Unix. It was formed in 1988 and merged with X/Open in 1996, to become The Open Group. Despit ...

Research Institute and

Apple Computer Apple Inc. is an American multinational technology company headquartered in Cupertino, California, United States. Apple is the largest technology company by revenue (totaling in 2021) and, as of June 2022, is the world's biggest company b ...

in February 1996, to port

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 ...

to the

PowerPC PowerPC (with the backronym Performance Optimization With Enhanced RISC – Performance Computing, sometimes abbreviated as PPC) is a reduced instruction set computer (RISC) instruction set architecture (ISA) created by the 1991 Apple Inc., App ...

platform, and

Macintosh The Mac (known as Macintosh until 1999) is a family of personal computers designed and marketed by Apple Inc., Apple Inc. Macs are known for their ease of use and minimalist designs, and are popular among students, creative professionals, and ...

computers. The name refers to the

Linux kernel The Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally authored in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU ope ...

being adapted to run as a server hosted on the Mach

microkernel In computer science, a microkernel (often abbreviated as μ-kernel) is the near-minimum amount of software that can provide the mechanisms needed to implement an operating system (OS). These mechanisms include low-level address space management, ...

, version 3.0.

History

MkLinux started as a project sponsored by Apple Computer and OSF Research Institute, to get "Linux on Mach" ported to the Macintosh computer and for Apple to explore alternative kernel technologies on the Mac platform. At the time, there was no officially sponsored PowerPC port of Linux, and none specifically for Macintosh hardware. The OSF Institute, owner of the Mach

and several other

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, and ot ...

-based technologies, was interested in promoting Mach on other platforms. Unlike the design of the later

macOS macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and lapt ...

versions 10 and newer (not to be confused with the contemporaneous

Mac OS Two major famlies of Mac operating systems were developed by Apple Inc. In 1984, Apple debuted the operating system that is now known as the "Classic" Mac OS with its release of the original Macintosh System Software. The system, rebranded "M ...

versions 9 and older), MkLinux was designed to take full advantage of the Mach microkernel. By contrast, macOS inherited from

NeXTSTEP NeXTSTEP is a discontinued object-oriented, multitasking operating system based on the Mach kernel and the UNIX-derived BSD. It was developed by NeXT Computer in the late 1980s and early 1990s and was initially used for its range of proprieta ...

the

hybrid kernel A hybrid kernel is an operating system Kernel (computer science), kernel architecture that attempts to combine aspects and benefits of microkernel and monolithic kernel architectures used in computer operating systems. Overview The traditional ker ...

named XNU, wherein the BSD kernel personality is grafted on Mach, which are both run together in a single kernel

address space In computing, an address space defines a range of discrete addresses, each of which may correspond to a network host, peripheral device, disk sector, a memory cell or other logical or physical entity. For software programs to save and retrieve st ...

for faster performance. The effort was spearheaded by Apple's VP of Development Tools

Ike Nassi Isaac Robert "Ike" Nassi, born 1949 in Brooklyn, New York, is currently CTO and chairman at TidalScale, Inc. in Campbell, CA, and Adjunct Professor of Computer Science at the University of California, Santa Cruz. He is known for creating (with Ben ...

and Brett Halle at Apple, and development was later split between two main people: Michael Burg on device drivers and distribution at Apple in Cupertino, California; and Nick Stephen on Mach porting and development at the OSF in

Grenoble lat, Gratianopolis , commune status = Prefecture and commune , image = Panorama grenoble.png , image size = , caption = From upper left: Panorama of the city, Grenoble’s cable cars, place Saint- ...

, France. Other key individuals to work on the project included François Barbou at OSF, and Vicki Brown and Gilbert Coville at Apple. MkLinux was officially announced at the 1996 World Wide Developers Conference (WWDC). A free CD containing a binary distribution of MkLinux was handed out to the attendees. In mid 1998, the community-led MkLinux Developers Association took over development of the operating system. The MkLinux distribution is much too large for casual users to have downloaded via the slow

dial-up Internet access Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network (PSTN) to establish a connection to an Internet service provider (ISP) by dialing a telephone number on a conventional telepho ...

of the day, even using 56k modems. However, the official CDs were available in a book from Prime Time Freeware, published in English and in Japanese. The book covers installation, management, and use of the OS, and serves as a hardcopy manual. Apple later released the

Open Firmware Open Firmware is a standard defining the interfaces of a computer firmware system, formerly endorsed by the Institute of Electrical and Electronics Engineers (IEEE). It originated at Sun Microsystems, where it was known as OpenBoot, and has bee ...

-based

Power Macintosh The Power Macintosh, later Power Mac, is a family of personal computers designed, manufactured, and sold by Apple Computer as the core of the Macintosh brand from March 1994 until August 2006. Described by ''MacWorld'' as "the most important te ...

computers, an official PowerPC branch of the Linux kernel was created and was spearheaded by the LinuxPPC project. MkLinux and LinuxPPC developers traded a lot of ideas back and forth as both worked on their own ways of running Linux.

Debian Debian (), also known as Debian GNU/Linux, is a Linux distribution composed of free and open-source software, developed by the community-supported Debian Project, which was established by Ian Murdock on August 16, 1993. The first version of D ...

also released a traditional monolithic kernel distribution for PowerPC—as did

SUSE SUSE ( , ) is a German-based multinational open-source software company that develops and sells Linux products to business customers. Founded in 1992, it was the first company to market Linux for enterprise. It is the developer of SUSE Linux Ent ...

, and

Terra Soft Solutions Fixstars Solutions, Inc. is a software and services company specializing in multi-core processors, particularly in Nvidia's GPU and CUDA environment, IBM Power7, and Cell. They also specialize in solid-state drives and currently manufacture the ...

with

Yellow Dog Linux Yellow Dog Linux (YDL) is a discontinued free and open-source operating system for high-performance computing on multi-core processor computer architectures, focusing on GPU systems and computers using the POWER7 processor. The original develope ...

. When Apple dropped support for MkLinux, the developer community struggled to improve the Mach kernel, and to support various Power Macintosh models. MkLinux continued to be the only option for Macintosh

NuBus NuBus (pron. 'New Bus') is a 32-bit parallel computer bus, originally developed at MIT and standardized in 1987 as a part of the NuMachine workstation project. The first complete implementation of the NuBus was done by Western Digital for th ...

computers until June 2000, when PPC/Linux for NuBus Power Macs was released.

Reception

''MacTech'' magazine observed this of the general state of Linux on Macintosh in 1999: "Seen as a Windows NT or commercial Unix killer in some circles, Linux also promises to give the Mac OS a boost in the right direction and might even give Mac OS X Server a run for its money among Apple shops." The installation process was seen as "either smooth as silk or very, very rough" and that it "can also be slightly more difficult to recompile the MkLinux kernel because of the extra steps to placate the Mach microkernel." MkLinux had greater hardware compatibility than LinuxPPC at the time, supporting both NuBus and PCI Macintosh systems whereas LinuxPPC only supports PCI. Compared to LinuxPPC, MkLinux was generally known as having a performance cost due to the overhead of the Mach kernel. The Linux environment was found to provide a potentially adequate desktop suite, but one that forgoes the entire Macintosh experience in favor of pure Linux.

Legacy

MkLinux is the first official attempt by Apple to support a

free and open-source software Free and open-source software (FOSS) is a term used to refer to groups of software consisting of both free software and open-source software where anyone is freely licensed to use, copy, study, and change the software in any way, and the source ...

project. The work done with the Mach 3.0 kernel in MkLinux is said to have been extremely helpful in the initial porting of NeXTSTEP to the Macintosh hardware platform, which would later become macOS.

Releases

References

External links