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62-484: Advanced Configuration and Power Interface ( ACPI ) is an open standard that operating systems can use to discover and configure computer hardware components, to perform power management (e.g. putting unused hardware components to sleep), auto configuration (e.g. Plug and Play and hot swapping ), and status monitoring. It was first released in December 1996. ACPI aims to replace Advanced Power Management (APM),

124-408: A "Function Fixed Hardware (FFH) Interface", or a platform-independent hardware programming model which relies on platform-specific ACPI Machine Language (AML) provided by the original equipment manufacturer (OEM). Function Fixed Hardware interfaces are platform-specific features, provided by platform manufacturers for the purposes of performance and failure recovery. Standard Intel -based PCs have

186-494: A "free software and open standards law." The decree includes the requirement that the Venezuelan public sector must use free software based on open standards, and includes a definition of open standard: Multiprocessor Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system . The term also refers to the ability of a system to support more than one processor or

248-681: A common patent policy under the banner of the WSC . However, the ITU-T definition should not necessarily be considered also applicable in ITU-R, ISO and IEC contexts, since the Common Patent Policy does not make any reference to "open standards" but rather only to "standards." In section 7 of its RFC 2026, the IETF classifies specifications that have been developed in a manner similar to that of

310-402: A data format which is made public, is thoroughly documented and neutral with regard to the technological tools needed to peruse the same data. The E-Government Interoperability Framework (e-GIF) defines open standard as royalty-free according to the following text: While a universally agreed definition of "open standards" is unlikely to be resolved in the near future, the e-GIF accepts that

372-606: A definition of "open standards" needs to recognise a continuum that ranges from closed to open, and encompasses varying degrees of "openness." To guide readers in this respect, the e-GIF endorses "open standards" that exhibit the following properties: The e-GIF performs the same function in e-government as the Road Code does on the highways. Driving would be excessively costly, inefficient, and ineffective if road rules had to be agreed each time one vehicle encountered another. The Portuguese Open Standards Law, adopted in 2011, demands

434-535: A definition of open standards, which also is used in pan-European software development projects. It states: The French Parliament approved a definition of "open standard" in its "Law for Confidence in the Digital Economy." The definition is (Article 4): A clear royalty-free stance and far reaching requirements case is the one for India's Government 4.1 Mandatory Characteristics An Identified Standard will qualify as an "Open Standard", if it meets

496-725: A device or processor operates (D0 and C0, respectively), it can be in one of several power-performance states . These states are implementation-dependent. P0 is always the highest-performance state, with P1 to P n being successively lower-performance states. The total number of states is device or processor dependent, but can be no greater than 16. P-states have become known as SpeedStep in Intel processors, as PowerNow! or Cool'n'Quiet in AMD processors, and as PowerSaver in VIA processors. ACPI-compliant systems interact with hardware through either

558-421: A fixed function interface defined by Intel, which provides a set of core functionality that reduces an ACPI-compliant system's need for full driver stacks for providing basic functionality during boot time or in the case of major system failure. ACPI Platform Error Interface (APEI) is a specification for reporting of hardware errors, e.g. chipset, RAM to the operating system. ACPI defines many tables that provide

620-605: A full, irrevocable and irreversible way to the Portuguese State; e) There are no restrictions to its implementation. A Law passed by the Spanish Parliament requires that all electronic services provided by the Spanish public administration must be based on open standards. It defines an open standard as royalty-free, according to the following definition (ANEXO Definiciones k): An open standard fulfills

682-466: A high speed communication system ( Gigabit Ethernet is common). A Linux Beowulf cluster is an example of a loosely coupled system. Tightly coupled systems perform better and are physically smaller than loosely coupled systems, but have historically required greater initial investments and may depreciate rapidly; nodes in a loosely coupled system are usually inexpensive commodity computers and can be recycled as independent machines upon retirement from

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744-549: A master/slave multiprocessor system of microprocessors is the Tandy/Radio Shack TRS-80 Model 16 desktop computer which came out in February 1982 and ran the multi-user/multi-tasking Xenix operating system, Microsoft's version of UNIX (called TRS-XENIX). The Model 16 has two microprocessors: an 8-bit Zilog Z80 CPU running at 4 MHz, and a 16-bit Motorola 68000 CPU running at 6 MHz. When

806-478: A number of ways, including asymmetric multiprocessing (ASMP), non-uniform memory access (NUMA) multiprocessing, and clustered multiprocessing. In a master/slave multiprocessor system, the master CPU is in control of the computer and the slave CPU(s) performs assigned tasks. The CPUs can be completely different in terms of speed and architecture. Some (or all) of the CPUs can share a common bus, each can also have

868-541: A private bus (for private resources), or they may be isolated except for a common communications pathway. Likewise, the CPUs can share common RAM and/or have private RAM that the other processor(s) cannot access. The roles of master and slave can change from one CPU to another. Two early examples of a mainframe master/slave multiprocessor are the Bull Gamma 60 and the Burroughs B5000 . An early example of

930-598: A set of principles which have contributed to the exponential growth of the Internet and related technologies. The "OpenStand Principles" define open standards and establish the building blocks for innovation. Standards developed using the OpenStand principles are developed through an open, participatory process, support interoperability, foster global competition, are voluntarily adopted on a global level and serve as building blocks for products and services targeted to meet

992-714: Is determined by the market. The ITU-T is a standards development organization (SDO) that is one of the three sectors of the International Telecommunication Union (a specialized agency of the United Nations ). The ITU-T has a Telecommunication Standardization Bureau director's Ad Hoc group on IPR that produced the following definition in March 2005, which the ITU-T as a whole has endorsed for its purposes since November 2005: The ITU-T , ITU-R , ISO , and IEC have harmonized on

1054-399: Is generally used to denote that scenario. Other authors prefer to refer to the operating system techniques as multiprogramming and reserve the term multiprocessing for the hardware aspect of having more than one processor. The remainder of this article discusses multiprocessing only in this hardware sense. In Flynn's taxonomy , multiprocessors as defined above are MIMD machines. As

1116-557: Is here meant in the sense of fulfilling the following requirements: The Network Centric Operations Industry Consortium (NCOIC) defines open standard as the following: Specifications for hardware and/or software that are publicly available implying that multiple vendors can compete directly based on the features and performance of their products. It also implies that the existing open system can be removed and replaced with that of another vendor with minimal effort and without major interruption. The Danish government has attempted to make

1178-411: Is sometimes contrasted with multitasking , which may use just a single processor but switch it in time slices between tasks (i.e. a time-sharing system ). Multiprocessing however means true parallel execution of multiple processes using more than one processor. Multiprocessing doesn't necessarily mean that a single process or task uses more than one processor simultaneously; the term parallel processing

1240-506: Is then published in the form of RFC 6852 in January 2013. The European Union defined the term for use within its European Interoperability Framework for Pan-European eGovernment Services, Version 1.0 although it does not claim to be a universal definition for all European Union use and documentation. To reach interoperability in the context of pan-European eGovernment services, guidance needs to focus on open standards. The word "open"

1302-759: The GSM phones (adopted as a government standard), Open Group which promotes UNIX , and the Internet Engineering Task Force (IETF) which created the first standards of SMTP and TCP/IP. Buyers tend to prefer open standards which they believe offer them cheaper products and more choice for access due to network effects and increased competition between vendors. Open standards which specify formats are sometimes referred to as open formats . Many specifications that are sometimes referred to as standards are proprietary, and only available (if they can be obtained at all) under restrictive contract terms from

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1364-470: The Linux kernel —described ACPI as "a complete design disaster in every way". Open standard The terms open and standard have a wide range of meanings associated with their usage. There are a number of definitions of open standards which emphasize different aspects of openness, including the openness of the resulting specification, the openness of the drafting process, and the ownership of rights in

1426-685: The MultiProcessor Specification , and the Plug and Play BIOS (PnP) Specification. ACPI brings power management under the control of the operating system, as opposed to the previous BIOS-centric system that relied on platform-specific firmware to determine power management and configuration policies. The specification is central to the Operating System-directed configuration and Power Management ( OSPM ) system. ACPI defines hardware abstraction interfaces between

1488-607: The New Zealand , South African and the Venezuelan governments. On the standard organisation side, the World Wide Web Consortium (W3C) ensures that its specifications can be implemented on a royalty-free basis. Many definitions of the term standard permit patent holders to impose " reasonable and non-discriminatory licensing" royalty fees and other licensing terms on implementers or users of

1550-659: The USB ;3.0 support, logical processor idling support, and x2APIC support. Initially ACPI is exclusive to x86 architecture; Revision 5.0 of the ACPI specification was released in December 2011, which added the ARM architecture support. The revision 5.1 was released in July 2014. The latest specification revision is 6.5, which was released in August 2022. Microsoft's Windows 98

1612-611: The "Simplified BSD License" as stated in the IETF Trust Legal Provisions and Copyright FAQ based on RFC 5377. In August 2012, the IETF combined with the W3C and IEEE to launch OpenStand and to publish The Modern Paradigm for Standards. This captures "the effective and efficient standardization processes that have made the Internet and Web the premiere platforms for innovation and borderless commerce". The declaration

1674-466: The 68000 CPU. The Z-80 can be used to do other tasks. The earlier TRS-80 Model II , which was released in 1979, could also be considered a multiprocessor system as it had both a Z-80 CPU and an Intel 8021 microcontroller in the keyboard. The 8021 made the Model II the first desktop computer system with a separate detachable lightweight keyboard connected with by a single thin flexible wire, and likely

1736-705: The ACPI tables. To make use of the ACPI tables, the operating system must have an interpreter for the AML bytecode. A reference AML interpreter implementation is provided by the ACPI Component Architecture (ACPICA). At the BIOS development time, AML bytecode is compiled from the ASL (ACPI Source Language) code. The ACPI Component Architecture ( ACPICA ), mainly written by Intel's engineers, provides an open-source platform-independent reference implementation of

1798-532: The BIOS date is after January 1, 1999. Similarly, Linux kernel 2.6 may not use ACPI if the BIOS date is before January 1, 2001. Linux-based operating systems can provide handling of ACPI events via acpid. Once an OSPM-compatible operating system activates ACPI, it takes exclusive control of all aspects of power management and device configuration. The OSPM implementation must expose an ACPI-compatible environment to device drivers, which exposes certain system, device and processor states. The ACPI Specification defines

1860-495: The IETF and ITU-T explicitly refer to their standards as "open standards", while the others refer only to producing "standards". The IETF and ITU-T use definitions of "open standard" that allow "reasonable and non-discriminatory" patent licensing fee requirements. There are those in the open-source software community who hold that an "open standard" is only open if it can be freely adopted, implemented and extended. While open standards or architectures are considered non-proprietary in

1922-518: The IETF itself as being "open standards," and lists the standards produced by ANSI , ISO , IEEE , and ITU-T as examples. As the IETF standardization processes and IPR policies have the characteristics listed above by ITU-T, the IETF standards fulfill the ITU-T definition of "open standards." However, the IETF has not adopted a specific definition of "open standard"; both RFC 2026 and the IETF's mission statement (RFC 3935) talks about "open process," but RFC 2026 does not define "open standard" except for

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1984-665: The Xeon processors via a common pipe and the Opteron processors via independent pathways to the system RAM . Chip multiprocessors, also known as multi-core computing, involves more than one processor placed on a single chip and can be thought of the most extreme form of tightly coupled multiprocessing. Mainframe systems with multiple processors are often tightly coupled. Loosely coupled multiprocessor systems (often referred to as clusters ) are based on multiple standalone relatively low processor count commodity computers interconnected via

2046-613: The ability to allocate tasks between them. There are many variations on this basic theme, and the definition of multiprocessing can vary with context, mostly as a function of how CPUs are defined ( multiple cores on one die , multiple dies in one package , multiple packages in one system unit , etc.). According to some on-line dictionaries, a multiprocessor is a computer system having two or more processing units (multiple processors) each sharing main memory and peripherals, in order to simultaneously process programs. A 2009 textbook defined multiprocessor system similarly, but noting that

2108-511: The bus level. These CPUs may have access to a central shared memory (SMP or UMA ), or may participate in a memory hierarchy with both local and shared memory (SM)( NUMA ). The IBM p690 Regatta is an example of a high end SMP system. Intel Xeon processors dominated the multiprocessor market for business PCs and were the only major x86 option until the release of AMD 's Opteron range of processors in 2004. Both ranges of processors had their own onboard cache but provided access to shared memory;

2170-451: The cluster. Power consumption is also a consideration. Tightly coupled systems tend to be much more energy-efficient than clusters. This is because a considerable reduction in power consumption can be realized by designing components to work together from the beginning in tightly coupled systems, whereas loosely coupled systems use components that were not necessarily intended specifically for use in such systems. Loosely coupled systems have

2232-669: The computer to have an ACPI-compliant BIOS, and since Windows 8 , the S0ix/Modern Standby state was implemented. Windows operating systems use acpi.sys to access ACPI events. The 2.4 series of the Linux kernel had only minimal support for ACPI, with better support implemented (and enabled by default) from kernel version 2.6.0 onwards. Old ACPI BIOS implementations tend to be quite buggy, and consequently are not supported by later operating systems. For example, Windows 2000 , Windows XP , and Windows Server 2003 only use ACPI if

2294-649: The degree of openness will be taken into account when selecting an appropriate standard: The UK government 's definition of open standards applies to software interoperability, data and document formats. The criteria for open standards are published in the "Open Standards Principles" policy paper and are as follows. The Cabinet Office in the UK recommends that government departments specify requirements using open standards when undertaking procurement exercises in order to promote interoperability and re-use, and avoid technological lock-in. The Venezuelan Government approved

2356-497: The device's firmware (e.g. BIOS , UEFI ), the computer hardware components, and the operating systems . Internally, ACPI advertises the available components and their functions to the operating system kernel using instruction lists (" methods ") provided through the system firmware ( UEFI or BIOS ), which the kernel parses. ACPI then executes the desired operations written in ACPI Machine Language (such as

2418-741: The first keyboard to use a dedicated microcontroller, both attributes that would later be copied years later by Apple and IBM. In multiprocessing, the processors can be used to execute a single sequence of instructions in multiple contexts ( single instruction, multiple data or SIMD, often used in vector processing ), multiple sequences of instructions in a single context ( multiple instruction, single data or MISD, used for redundancy in fail-safe systems and sometimes applied to describe pipelined processors or hyper-threading ), or multiple sequences of instructions in multiple contexts ( multiple instruction, multiple data or MIMD). Tightly coupled multiprocessor systems contain multiple CPUs that are connected at

2480-506: The following conditions: The South African Government approved a definition in the "Minimum Interoperability Operating Standards Handbook" (MIOS). For the purposes of the MIOS, a standard shall be considered open if it meets all of these criteria. There are standards which we are obliged to adopt for pragmatic reasons which do not necessarily fully conform to being open in all respects. In such cases, where an open standard does not yet exist,

2542-581: The following criteria: Italy has a general rule for the entire public sector dealing with Open Standards, although concentrating on data formats, in Art. 68 of the Code of the Digital Administration ( Codice dell'Amministrazione Digitale ) [applications must] allow representation of data under different formats, at least one being an open data format. [...] [it is defined] an open data format,

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2604-425: The following four global "Gx" states and six sleep "Sx" states for an ACPI-compliant computer system: The specification also defines a Legacy state: the state of an operating system which does not support ACPI. In this state, the hardware and power are not managed via ACPI, effectively disabling ACPI. The device states D0 – D3 are device dependent: The CPU power states C0 – C3 are defined as follows: While

2666-502: The initialization of hardware components) using an embedded minimal virtual machine . Intel , Microsoft and Toshiba originally developed the standard, while HP , Huawei and Phoenix also participated later. In October 2013, ACPI Special Interest Group (ACPI SIG), the original developers of the ACPI standard, agreed to transfer all assets to the UEFI Forum , in which all future development will take place. The latest version of

2728-573: The interface between an ACPI-compliant operating system and system firmware ( BIOS or UEFI ). This includes RSDP, RSDT, XSDT, FADT, FACS, DSDT, SSDT, MADT, and MCFG, for example. The tables allow description of system hardware in a platform-independent manner, and are presented as either fixed-formatted data structures or in AML. The main AML table is the DSDT (differentiated system description table). The AML can be decompiled by tools like Intel's iASL (open-source, part of ACPICA) for purposes like patching

2790-400: The needs of markets and consumers. This drives innovation which, in turn, contributes to the creation of new markets and the growth and expansion of existing markets. There are five, key OpenStand Principles, as outlined below: 1. Cooperation Respectful cooperation between standards organizations, whereby each respects the autonomy, integrity, processes, and intellectual property rules of

2852-667: The operating system–related ACPI code. The ACPICA code is used by Linux, Haiku , ArcaOS and FreeBSD , which supplement it with their operating-system specific code. The first revision of the ACPI specification was released in December 1996, supporting 16, 24 and 32-bit addressing spaces. It was not until August 2000 that ACPI received 64-bit address support as well as support for multiprocessor workstations and servers with revision 2.0. In 1999, then Microsoft CEO Bill Gates stated in an e-mail that Linux would benefit from ACPI without them having to do work and suggested to make it Windows-only. In September 2004, revision 3.0

2914-411: The organization that owns the copyright on the specification. As such these specifications are not considered to be fully open . Joel West has argued that "open" standards are not black and white but have many different levels of "openness". A more open standard tends to occur when the knowledge of the technology becomes dispersed enough that competition is increased and others are able to start copying

2976-711: The others. 2. Adherence to Principles – Adherence to the five fundamental principles of standards development, namely 3. Collective Empowerment Commitment by affirming standards organizations and their participants to collective empowerment by striving for standards that: 4. Availability Standards specifications are made accessible to all for implementation and deployment. Affirming standards organizations have defined procedures to develop specifications that can be implemented under fair terms. Given market diversity, fair terms may vary from royalty-free to fair, reasonable, and non-discriminatory terms (FRAND). 5. Voluntary Adoption Standards are voluntarily adopted and success

3038-441: The processors may share "some or all of the system’s memory and I/O facilities"; it also gave tightly coupled system as a synonymous term. At the operating system level, multiprocessing is sometimes used to refer to the execution of multiple concurrent processes in a system, with each process running on a separate CPU or core, as opposed to a single process at any one instant. When used with this definition, multiprocessing

3100-647: The purpose of defining what documents IETF standards can link to. RFC 2026 belongs to a set of RFCs collectively known as BCP 9 (Best Common Practice, an IETF policy). RFC 2026 was later updated by BCP 78 and 79 (among others). As of 2011 BCP 78 is RFC 5378 (Rights Contributors Provide to the IETF Trust), and BCP 79 consists of RFC 3979 (Intellectual Property Rights in IETF Technology) and a clarification in RFC 4879. The changes are intended to be compatible with

3162-485: The sense that the standard is either unowned or owned by a collective body, it can still be publicly shared and not tightly guarded. The typical example of "open source" that has become a standard is the personal computer originated by IBM and now referred to as Wintel , the combination of the Microsoft operating system and Intel microprocessor. There are three others that are most widely accepted as "open" which include

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3224-460: The standard 6.5 was released in August 2022. The firmware-level ACPI has three main components: the ACPI tables, the ACPI BIOS, and the ACPI registers. The ACPI BIOS generates ACPI tables and loads ACPI tables into main memory . Much of the firmware ACPI functionality is provided in bytecode of ACPI Machine Language (AML), a Turing-complete , domain-specific low-level language , stored in

3286-525: The standard. For example, the rules for standards published by the major internationally recognized standards bodies such as the Internet Engineering Task Force (IETF), International Organization for Standardization (ISO), International Electrotechnical Commission (IEC), and ITU-T permit their standards to contain specifications whose implementation will require payment of patent licensing fees. Among these organizations, only

3348-493: The standard. The term "standard" is sometimes restricted to technologies approved by formalized committees that are open to participation by all interested parties and operate on a consensus basis. The definitions of the term open standard used by academics, the European Union , and some of its member governments or parliaments such as Denmark , France , and Spain preclude open standards requiring fees for use, as do

3410-739: The symmetry (or lack thereof) in a given system. For example, hardware or software considerations may require that only one particular CPU respond to all hardware interrupts, whereas all other work in the system may be distributed equally among CPUs; or execution of kernel-mode code may be restricted to only one particular CPU, whereas user-mode code may be executed in any combination of processors. Multiprocessing systems are often easier to design if such restrictions are imposed, but they tend to be less efficient than systems in which all CPUs are utilized. Systems that treat all CPUs equally are called symmetric multiprocessing (SMP) systems. In systems where all CPUs are not equal, system resources may be divided in

3472-502: The system is booted, the Z-80 is the master and the Xenix boot process initializes the slave 68000, and then transfers control to the 68000, whereupon the CPUs change roles and the Z-80 becomes a slave processor responsible for all I/O operations including disk, communications, printer and network, as well as the keyboard and integrated monitor, while the operating system and applications run on

3534-840: The tables for expanding OS compatibility. The Root System Description Pointer (RSDP) is located in a platform-dependent manner, and describes the rest of the tables. A custom ACPI table called the Windows Platform Binary Table (WPBT) is used by Microsoft to allow vendors to add software into the Windows OS automatically. Some vendors, such as Lenovo , have been caught using this feature to install harmful software such as Superfish . Samsung shipped PCs with Windows Update disabled. Windows versions older than Windows 7 do not support this feature, but alternative techniques can be used. This behavior has been compared to rootkits . In November 2003, Linus Torvalds —author of

3596-702: The technology as they implement it. This occurred with the Wintel architecture as others were able to start imitating the software. Less open standards exist when a particular firm has much power (not ownership) over the standard, which can occur when a firm's platform "wins" in standard setting or the market makes one platform most popular. On August 12, 2012, the Institute of Electrical and Electronics Engineers (IEEE), Internet Society (ISOC), World Wide Web Consortium (W3C), Internet Engineering Task Force (IETF) and Internet Architecture Board (IAB), jointly affirmed

3658-420: The term "multiprocessor" normally refers to tightly coupled systems in which all processors share memory, multiprocessors are not the entire class of MIMD machines, which also contains message passing multicomputer systems. In a multiprocessing system, all CPUs may be equal, or some may be reserved for special purposes. A combination of hardware and operating system software design considerations determine

3720-667: The use of Open Standards, and is applicable to sovereign entities, central public administration services (including decentralized services and public institutes), regional public administration services and the public sector. In it, Open Standards are defined thus: a) Its adoption is fruit off an open decision process accessible to all interested parties; b) The specifications document must have been freely published, allowing its copy, distribution and use without restrictions; c) The specifications document cannot cover undocumented actions of processes; d) The applicable intellectual property rights, including patents, have been made available in

3782-465: Was released, bringing to the ACPI specification support for SATA interfaces, PCI Express bus, multiprocessor support for more than 256 processors, ambient light sensors and user-presence devices, as well as extending the thermal model beyond the previous processor-centric support. Released in June 2009, revision 4.0 of the ACPI specification added various new features to the design; most notable are

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3844-581: Was the first operating system to implement ACPI, but its implementation was somewhat buggy or incomplete, although some of the problems associated with it were caused by the first-generation ACPI hardware. Other operating systems, including later versions of Windows , macOS (x86 macOS only), eComStation , ArcaOS , FreeBSD (since FreeBSD 5.0), NetBSD (since NetBSD 1.6), OpenBSD (since OpenBSD 3.8), HP-UX , OpenVMS , Linux , GNU/Hurd and PC versions of Solaris , have at least some support for ACPI. Some newer operating systems, like Windows Vista , require

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