Editing Mach (kernel) (section)

{{Short description|Operating system microkernel}}
{{Use mdy dates|date=July 2024}}
{{Infobox software
| name = Mach
| logo = 
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| author = 
| developer = [[Richard Rashid]]<br /> [[Avie Tevanian]]
| released = {{Start date and age|1985}}
| discontinued = 
| latest release version = 3.0
| latest release date = {{Start date and age|1994}}
| latest preview version = 
| latest preview date = <!-- {{Start date and age|YYYY|MM|DD}} -->
| frequently updated = 
| programming language = 
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| platform = [[IA-32]], [[x86-64]], [[MIPS architecture|MIPS]], [[ARM32]], [[Aarch64]], [[m88k]]
| size = 
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| genre = [[Microkernel]]
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| website = {{URL|https://www.cs.cmu.edu/afs/cs/project/mach/public/www/mach.html|The Mach Project}}
| Institution = 
}}
'''Mach''' ({{IPAc-en|m|ɑː|k}})<ref name="JyEdfG">{{cite dictionary|title=Mach: Define Mach at Dictionary.com|url=http://www.dictionary.com/browse/mach|dictionary=Dictionary.com|access-date=December 12, 2016}}</ref> is an [[kernel (operating system)|operating system kernel]] developed at [[Carnegie Mellon University]] by [[Richard Rashid]] and [[Avie Tevanian]] to support [[operating system]] research, primarily [[distributed computing|distributed]] and [[parallel computing]]. Mach is often considered one of the earliest examples of a [[microkernel]]. However, not all versions of Mach are microkernels. Mach's derivatives are the basis of the operating system kernel in [[GNU Hurd]] and of [[Apple Inc.|Apple]]'s [[XNU]] kernel used in [[macOS]], [[iOS]], [[iPadOS]], [[tvOS]], and [[watchOS]].

The project at Carnegie Mellon ran from 1985 to 1994,<ref name="HyeRgh">{{cite web|url=https://www.cs.cmu.edu/afs/cs/project/mach/public/www/mach.html|title=CMU CS Project Mach Home Page}}</ref> ending with Mach 3.0, which is a true [[microkernel]]. Mach was developed as a replacement for the kernel in the [[Berkeley Software Distribution|BSD]] version of [[Unix]], not requiring a new operating system to be designed around it. Mach and its derivatives exist within several commercial operating systems. These include all using the XNU operating system kernel which incorporates an earlier non-microkernel Mach as a major component. The Mach [[virtual memory]] management system was also adopted in 4.4BSD by the BSD developers at [[Computer Systems Research Group|CSRG]],<ref name="JuRtBN">{{cite book|url=https://books.google.com/books?id=6rjd2ZxE1vYC&pg=PT200|title=The Design and Implementation of the 4.4 BSD Operating System|first1=Marshall Kirk|last1=McKusick|author-link1=Kirk McKusick|first2=Keith|last2=Bostic|author-link2=Keith Bostic (software engineer)|first3=Michael J.|last3=Karels|author-link3=Michael J. Karels|first4=John S.|last4=Quarterman|author-link4=John Quarterman|page=123|date=April 30, 1996|isbn=978-0-7686-8494-0|publisher=[[Addison-Wesley]]}}</ref> and appears in modern BSD-derived Unix systems such as [[FreeBSD]].

Mach is the logical successor to Carnegie Mellon's [[Accent kernel]]. Mach's lead developer Richard Rashid has been employed at [[Microsoft]] since 1991; he founded the [[Microsoft Research]] division. Co-founding Mach developer Avie Tevanian, was formerly head of software at [[NeXT]], then Chief Software Technology Officer at [[Apple Inc.]] until March 2006.<ref name="IghTyn">{{cite news |url=http://blog.sfgate.com/techchron/2006/03/27/adios-avie/ |title=Adios Avie|author=Al Saracevic|publisher=The Technology Chronicles |date=March 27, 2006 |archive-url=https://web.archive.org/web/20111204041437/http://blog.sfgate.com/techchron/2006/03/27/adios-avie/ |archive-date=December 4, 2011 |url-status=dead}}</ref><ref name="HyeRgh" />