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79-473: A key concept in the AS/400 platform is Technology Independent Machine Interface (TIMI), a platform-independent instruction set architecture (ISA) that is translated to native machine language instructions. The platform has used this capability to change the underlying processor architecture without breaking application compatibility. Early systems were based on a 48-bit CISC instruction set architecture known as

158-662: A single-level store , and the tight integration of a relational database into the operating system. OS/400 was developed alongside the AS/400 hardware platform beginning in December 1985. Development began in the aftermath of the failure of the Fort Knox project, which left IBM without a competitive midrange system. During the Fort Knox project, a skunkworks project was started at Rochester by engineers, who succeeded in developing code which allowed System/36 applications to run on top of

237-491: A backing store. Other open source databases have been ported to IBM i, including PostgreSQL , MongoDB and Redis . These databases run on the PASE environment, and are independent of the operating system's integrated database features. IBM i supports TCP/IP networking in addition to the proprietary IBM Systems Network Architecture . IBM i systems were historically accessed and managed through IBM 5250 terminals attached to

316-554: A pair of AS/400-specific processors were designed at IBM Endicott and IBM Rochester, known as Cobra (for low end systems) and Muskie (for high end systems) respectively. These became the initial implementations of the IBM RS64 processor line. The RS64 series continued to be developed as a separate product line at IBM until the POWER4 merged both the RS64 and POWER product lines together. Despite

395-596: A project named Fort Knox commenced, which was intended to consolidate the System/36 , the System/38 , the IBM 8100 , the Series/1 and the IBM 4300 series into a single product line based around an IBM 801 -based processor codenamed Iliad , while retaining backwards compatibility with all the systems it was intended to replace. A new operating system would be created for Fort Knox, but

474-680: A rewrite of most of the code below the TIMI . Early versions of OS/400 inherited the Horizontal and Vertical Microcode layers of the System/38, although they were renamed to the Horizontal Licensed Internal Code (HLIC) and Vertical Licensed Internal Code (VLIC) respectively. The port to the new hardware led to the IMPI instruction set and the horizontal microcode implementing it being replaced by

553-614: A single address set which is the single-level store concept. Later generations of hardware are also capable of supporting various guest operating systems, including SSP , AIX , Linux , Microsoft Windows 2000 and Windows Server 2003 . While OS/400, AIX, and Linux are supported on the POWER processors on LPARs (logical partitions) , Windows is supported with either single-processor internal blade servers (IXS) or externally linked multiple-processor servers (IXA and iSCSI). SSP guests were supported using emulation from OS/400 V3R6 through V4R4 using

632-414: A single product line named IBM Power Systems . The name "AS/400" is sometimes used informally to refer to the IBM i operating system running on modern Power Systems hardware. In the early 1980s, IBM management became concerned that IBM's large number of incompatible midrange computer systems was hurting the company's competitiveness, particularly against Digital Equipment Corporation 's VAX . In 1982,

711-569: Is IBM's internal name for this layer, and as the name suggests, began as an evolution of the System/38 Control Program Facility . The XPF is mostly implemented in PL/MI , although other languages are also used. PASE (Portable Applications Solutions Environment) provides binary compatibility for user mode AIX executables which do not interact directly with the AIX kernel, and supports

790-460: Is a virtual instruction set independent of the underlying machine instruction set of the CPU. User-mode programs contain both TIMI instructions and the machine instructions of the CPU, thus ensuring hardware independence. This is conceptually somewhat similar to the virtual machine architecture of programming environments such as Java and .NET . Unlike some other virtual-machine architectures in which

869-421: Is addressed with 64-bit pointers. This was necessary since all IBM i jobs (i.e. processes) typically share the same address space. PASE applications do not use the hardware-independent TIMI instructions, and are instead compiled directly to Power machine code. Ports of open source software to IBM i typically target PASE instead of the native IBM i APIs in order to simplify porting. Open source software for IBM i

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948-655: Is similar to the Unix / Linux concept of volume groups ; however, with IBM i it is typical for all disk drives to be assigned to a single ASP. Security in IBM i is defined in terms of authorities , which represents the permission to carry out a specific action on a specific object. Authorities can be granted to individual users (known as user profiles ), groups (known as group profiles ) or all users ( public authorities). Related objects can be grouped together in an authorization list , making it possible to grant authorities on all objects in

1027-649: Is typically packaged using the RPM package format, and installed with the YUM package manager . PASE is distinct from the Qshell environment, which is an implementation of a Unix shell and associated utilities built on top of IBM i's native POSIX-compatible APIs. Introduced in 1994, the Advanced/36 platform ran unmodified System/36 applications and the SSP operating system in emulation on top of

1106-497: The 5 signifying the use of POWER5 processors, was introduced, replacing the eServer iSeries brand. Successive generations of iSeries and pSeries hardware converged until they were essentially the same hardware sold under different names and with different operating systems. Some i5 servers were still using the AS/400-specific IBM Machine Type (MT/M 9406-520), and were able to run AIX in an LPar along i5/OS, while

1185-502: The Advanced 36 Machine environment which ran System/36 SSP applications in emulation. IBM often uses different names for the TIMI, SLIC and XPF in documentation and marketing materials, for example, the IBM i 7.4 documentation refers to them as the IBM i Machine Interface , IBM i Licensed Internal Code and IBM i Operating System respectively. The TIMI isolates users and applications from

1264-476: The Internal Microprogrammed Interface (IMPI), originally developed for the System/38. In 1991, the company introduced a new version of the system running on a series of 64-bit PowerPC -derived CPUs, the IBM RS64 family. Due to the use of TIMI, applications for the original CISC-based programs continued to run on the new systems without modification, as the TIMI code can be re-translated to

1343-578: The System/370 -style Internal Microprogrammed Interface (IMPI) instruction set and the microcode used to implement it. In 1991, at the request of IBM president Jack Kuehler , a team under the leadership of Frank Soltis delivered a proposal to adapt the 64-bit PowerPC architecture to support the needs of the AS/400 platform. Their extensions to the PowerPC architecture, known as Amazon (and later as PowerPC AS ), were approved by IBM management instead of

1422-496: The " everything is a file " principle of Unix and its derivatives , on IBM i everything is an object (with built-in persistence and garbage collection). IBM uses a single-level store virtual memory architecture in the AS/400 platform. For 64-bit PowerPC processors, the virtual address resides in the rightmost 64 bits of a pointer while it was 48 bits in the S/38 and CISC AS/400. The 64-bit address space references main memory and disk as

1501-538: The 1990s and 2000s. As part of the 2004 rebranding to eServer i5 , OS/400 was renamed to i5/OS ; the 5 signifying the use of POWER5 processors. The first release of i5/OS, V5R3, was described by IBM as "a different name for the same operating system". In 2006, IBM rebranded the AS/400 line one last time to System i . In April 2008, IBM consolidated the System i with the System p platform to create IBM Power Systems . At

1580-506: The 32-bit and 64-bit AIX Application Binary Interfaces . PASE was first included in a limited and undocumented form in the V4R3 release of OS/400 to support a port of Smalltalk . It was first announced to customers at the time of the V4R5 release, by which time it had gained significant additional functionality. PASE consists of the AIX userspace running on top of a system call interface implemented by

1659-520: The 64-bit RS64 architecture in 1995. Applications compiled on systems using the IMPI instruction set could run on top of the newer RS64 systems without any code changes, recompilation or emulation, while also allowing those applications to avail of 64-bit addressing. There are two different formats of TIMI instructions, known as the Original Machine Interface (OMI) and New Machine Interface (NMI) formats. OMI instructions are essentially

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1738-546: The 9370 served as an impetus for the creation of the much more successful AS/400 midrange systems. While becoming part of the IBM Enterprise Systems Architecture in 1988 ("ES/9370" like "ES/4300" and "ES/3090"), the 9370s weren't XA systems. In 1990 IBM announced the " ES/9000 " series; the rack-mounted models 120-170 with 31-bit Enterprise Systems Architecture (ESA) and ESCON were the suggested upgrades for ES/9370 users. The original 9370 hardware

1817-601: The Advanced 36 Machine facility of the operating system, a feature distinct from the System/36 Environment compatibility layer which requires System/36 software to be recompiled. IBM i#TIMI IBM i (the i standing for integrated ) is an operating system developed by IBM for IBM Power Systems . It was originally released in 1988 as OS/400 , as the sole operating system of the IBM AS/400 line of systems. It

1896-517: The Advanced/36 product line as a whole. The Advanced 36 Machine feature is distinct from the System/36 Environment introduced in the initial OS/400 release and still supported in current IBM i versions. Prior to the Advanced/36, the System/36 line used two different processors in each system - the Main Storage Processor (MSP) which ran most of the SSP operating system as well as user code, and

1975-498: The C-RISC design for development into the next AS/400 processor architecture. These extensions include support for tagged memory, as well as assistance for decimal arithmetic. IBM initially attempted to create a single PowerPC implementation for both AS/400 and high-end RS/6000 systems known as Belatrix . The Belatrix project proved to be too ambitious, and was cancelled when it became apparent that it would not deliver on schedule. Instead,

2054-791: The Control Storage Processor (CSP) which ran so-called "microcode" which implemented core operating system functionality as well as I/O. The CSP microcode was invoked from the MSP through the use of the Supervisor Call (SVC) instruction. On the Advanced/36, the CSP microcode was reimplemented inside the SLIC. An MSP emulator was also built into the SLIC, sometimes referred to as the Technology Independent Emulation Interface . Even with

2133-634: The Fort Knox hardware. In addition to adding support for System/36 applications, some of the user interface and ease-of-use features from the System/36 were carried over to the new operating system. Silverlake was available for field test in June 1988, and was officially announced in August of that year. By that point, it had been renamed to the Application System/400 , and the operating system had been named Operating System/400 . The port to PowerPC required

2212-552: The HLIC code, and most of the VLIC code. Owing to the amount of work needed to implement the SLIC, IBM Rochester hired several hundred C++ programmers for the project, who worked on the SLIC in parallel to new revisions of the VLIC for the CISC AS/400 systems. The first release of OS/400 to support PowerPC-based hardware was V3R6. The AS/400 product line was rebranded multiple times throughout

2291-413: The IBM 9370 as a " super-mini computer " for commercial and engineering/scientific use—compact, rack-mounted, designed for an office environment, not needing a data center to be used. At the time of announcement the systems were positioned between IBM's midrange systems ( IBM System/36 and IBM System/38 ), and the IBM 4300 mainframe series in performance. The IBM 9370 was partially a replacement for

2370-480: The OS/400 SLIC using hardware which was mostly identical to that of contemporary AS/400 systems. This functionality was incorporated into OS/400 itself from V3R6 through V4R4, making it possible to run up to four System/36 "virtual machines" (to use IBM's term) using the so-called Advanced 36 Machine feature of the operating system. Support was discontinued in the V4R5 release, coinciding with IBM's discontinuation of

2449-664: The PowerPC AS instruction set and its implementation in PowerAS processors. This required the VLIC to be rewritten to target PowerPC instead of IMPI, and for the operating system functionality previously implemented in the HLIC to be re-implemented elsewhere. This led to the HLIC and VLIC being replaced with a single layer named the System Licensed Internal Code (SLIC). The SLIC was implemented in an object-oriented style with over 2 million lines of C++ code, replacing some of

IBM AS/400 - Misplaced Pages Continue

2528-503: The PowerPC port, native support for the OMI format was removed, and replaced with a translator which converted OMI instructions into NMI instructions. The storing of the TIMI instructions alongside the native machine code instructions is known as observability . In 2008, the release of i5/OS V6R1 (later known as IBM i 6.1) introduced a number of changes to the TIMI layer which caused problems for third-party software which removed observability from

2607-416: The SLIC. The system call interfaces allows interoperability between PASE and native IBM i applications, for example, PASE applications can access the integrated database, or call native IBM i applications, and vice versa. During the creation of PASE, a new type of single level storage object named a Teraspace was added to the operating system, which allows each PASE process to have a private 1TiB space which

2686-458: The System/38, and when Fort Knox was cancelled, this project evolved into an official project to replace both the System/36 and System/38 with a single new hardware and software platform. The project became known as Silverlake (named for Silver Lake in Rochester, Minnesota ). The operating system for Silverlake was codenamed XPF (Extended CPF ), and had originally begun as a port of CPF to

2765-547: The TIMI, such as IBM i's integrated relational database. The SLIC implements IBM i's object-based storage model on top of a single-level store addressing scheme, which does not distinguish between primary and secondary storage, and instead manages all types of storage in a single virtual address space . The SLIC is primarily implemented in C++, and replaced the HLIC and VLIC layers used in versions of OS/400 prior to V3R6. The XPF consists of

2844-500: The also-not-so-successful IBM 8100 distributed processing engine. High-level 9370 models were mentioned as a substitution when low-level 4300 models were withdrawn from marketing 1987. Intended to be sold in large amounts as departmental machines (" VAX killers"), the 9370 initially suffered from lack of software and the failure of IBM to market it properly. Nevertheless, the systems were popular at least with users actually needing System/370 compatibility while not wanting to accept

2923-484: The amount of logic needed in each co-processor grew until the co-processors became the main processor, and the Iliad was relegated to the role of a support processor – thus failing the goal of consolidating on a single processor architecture. The Fort Knox project was ultimately cancelled in 1985. During the Fort Knox project, a skunkworks project was started at IBM Rochester by engineers who believed that Fort Knox's failure

3002-451: The application objects shipped to customers. The SLIC consists of the code which implements the TIMI on top of the IBM Power architecture. In addition to containing most of the functionality typically associated with an operating system kernel , it is responsible for translating TIMI instructions into machine code, and it also implements some high level functionality which is exposed through

3081-665: The code which implements the hardware-independent components of the operating system, which are compiled into TIMI instructions. Components of the XPF include the user interface, the Control Language , data management and query utilities, development tools and system management utilities. The XPF also contains the System/36 Environment and System/38 Environment , which provide backwards compatibility APIs and utilities for applications and data migrated from SSP and CPF systems. The XPF

3160-618: The default character encoding , but also provides support for ASCII , UCS-2 and UTF-16 . In IBM i, disk drives may be grouped into an auxiliary storage pool (ASP) in order to organize data to limit the impact of storage-device failures and to reduce recovery time. If a disk failure occurs, only the data in the pool containing the failed unit needs to be recovered. ASPs may also be used to improve performance by isolating objects with similar performance characteristics, for example journal receivers, in their own pool. By default, all disk drives are assigned to pool 1. The concept of IBM i pools

3239-464: The default Security Officer user profile, named QSECOFR , is the closest equivalent to the root user of a Unix-like operating system. IBM i can be set to use one of five levels of security, which control the extent to which the operating system's security features are enforced: The first three levels correspond to the security levels available in CPF and the initial releases of OS/400. Security level 40

IBM AS/400 - Misplaced Pages Continue

3318-415: The expense of a larger system (like e.g. smaller software houses) or with users (like some large IBM customers) preferring hierarchically structured distributed processing solutions rigidly managed by central communication controllers like IBM 37xx . By 1990 the 9370 line had around 6,300 installed systems and generated over 2 billion dollars in sales for IBM. The relatively lacklustre commercial success of

3397-568: The hardware-independent Extended Control Program Facility (XPF). These are divided by a hardware abstraction layer called the Technology Independent Machine Interface (TIMI). Later versions of the operating system gained additional layers, including an AIX compatibility layer named Portable Application Solutions Environment (originally known as the Private Address Space Environment ), and

3476-590: The integrated database - the so-called native interface , which is based on the database access model of the System/38, and SQL . The native interface consists of the Data Description Specifications (DDS) language, which is used to define schemas and the OPNQRYF command or QQQQRY query API. Certain Db2 for i features such as object-relational database management require SQL and cannot be accessed through

3555-444: The list by granting authorities on the authorization list. User profiles have an associated user class which dictates the set of default authorities available to that user profile. There are five standard user classes which, in order of increasing privilege, are: Workstation User , System Operator , System Programmer , Security Administrator and Security Officer . IBM i ships with a default user profile for each user class, and

3634-436: The move from IMPI to an entirely different processor architecture, the AS/400's Technology Independent Machine Interface (TIMI) mostly hid the changes from users and applications, and transparently recompiled applications for the new processor architecture. The port of OS/400 to the PowerPC AS architecture required a rewrite of most of the code below the TIMI due to the use of IMPI microcode to implement significant quantities of

3713-743: The native interface. IBM i has two separate query optimizers known as the Classic Query Engine (CQE) and SQL Query Engine (SQE). These are implemented inside the SLIC alongside a Query Dispatcher which selects the appropriate optimizer depending on the type of the query. Remote access through the native interface and SQL is provided by the Distributed Data Management Architecture (DDM) and Distributed Relational Database Architecture respectively. A storage engine for MySQL and MariaDB named IBMDB2I allows applications designed for those databases to use Db2 for i as

3792-502: The native operating system of the AS/400 platform, and was the sole operating system supported on the original AS/400 hardware. Many of the advanced features associated with the AS/400 are implemented in the operating system as opposed to the underlying hardware, which changed significantly throughout the life of the AS/400 platform. Features include a RDBMS ( Db2 for i ), a menu-driven interface, support for multiple users, block-oriented terminal support ( IBM 5250 ), and printers. Unlike

3871-409: The new systems' PowerPC Power ISA native machine code. The RS64 was replaced with POWER4 processors in 2001, which was followed by POWER5 and POWER6 in later upgrades. The AS/400 went through multiple re-branding exercises, finally becoming the System i in 2006. In 2008, IBM consolidated the separate System i and System p product lines (which had mostly identical hardware by that point) into

3950-667: The only part of IBM that Microsoft would be interested in was the AS/400 division. (At the time, many of Microsoft's business and financial systems ran on the AS/400 platform, rumored as ended around 1999 with the introduction of Windows 2000 .) According to Frank Soltis , one of the architects of the AS/400 platform, the AS/400's architecture is defined by five architectural principles. Most of these principles are inherited from System/38. The high-level instruction set (called TIMI for "Technology Independent Machine Interface" by IBM), allows application programs to take advantage of advances in hardware and software without recompilation. TIMI

4029-635: The operating system itself, such as the Source Edit Utility (SEU) text editor and Programming Development Manager . IBM also provides an Eclipse -based integrated development environment (IDE) for IBM i named IBM Rational Developer for i which runs on developer workstations instead of IBM i. Prior to the Eclipse-based IDE, IBM provided an IDE based on WorkFrame/2 which ran on OS/2 named CODE/400 and an IDE based on VisualAge which ran on Microsoft Windows systems. IBM i uses EBCDIC as

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4108-607: The operating system's low level code. This led to the creation of the System Licensed Internal Code (SLIC) - a new implementation of the lower levels of the operating system mostly written in C++ . The AS/400 family line was rebranded several times in the 1990s and 2000s as IBM introduced newer generations of hardware and operating system. In 1994, the AS/400 Advanced Series name was used for new models, followed by

4187-431: The operating systems and software of their existing platforms, they discovered that it would be impossible without making extensive changes to the Iliad processor for each individual operating system – changes which the Iliad's architects were unwilling to make. The proposed solution to this was to augment Iliad with operating system-specific co-processors which provided hardware support for a single operating system. However,

4266-429: The operating systems of each platform which Fort Knox was intended to replace would also be ported to the Iliad processor to allow customers to migrate their software to the new platform. The Fort Knox project proved to be overly ambitious, and ran into multiple delays and changes of scope. As the project advanced, the requirement to support IBM 8100 and Series/1 software was dropped. When IBM's engineers attempted to port

4345-454: The original CISC AS/400 48-bit processors) could be moved to a new processor (e.g., PowerPC 64-bit) without re-compilation. An application saved from the older 48-bit platform can simply be restored onto the new 64-bit platform where the operating system discards the old machine instructions and re-translates the TIMI instructions into 64-bit instructions for the new processor. The system's instruction set defines all pointers as 128-bit. This

4424-442: The overhead of emulation, the Advanced/36 systems were significantly faster than the original System/36 systems they replaced due to the performance of their PowerPC AS processors. IBM i features an integrated relational database currently known as IBM Db2 for IBM i . The database evolved from the non-relational System/38 database, gaining support for the relational model and SQL . The database originally had no name, instead it

4503-531: The p5 servers were able to run i5/OS respectively. The licensing for AIX and i5/OS was controlled in the firmware by the POWER hypervisor. The final rebranding occurred in 2006, when IBM rebranded the eServer i5 to System i . In April 2008, IBM introduced the IBM Power Systems line, which was a convergence of System i and System p product lines. The first Power Systems machines used the POWER6 processors; i5/OS

4582-473: The rebranding of the product line to AS/400e (the e standing for e-business ) in 1997. In 2000, eServer iSeries was introduced as part of its eServer branding initiative . The eServer iSeries was built on the POWER4 processor from the RS64 processors used by previous generations, meaning that the same processors were used in both the iSeries and pSeries platforms, the latter of which ran AIX . In 2004, eServer i5 (along with OS/400 becoming i5/OS )

4661-675: The same as the System/38 Machine interface instructions, whereas NMI instructions are lower-level, resembling the W-code intermediate representation format used by IBM's compilers. IBM partially documents the OMI instructions, whereas the NMI instructions are not officially documented. OMI instructions are used by the original AS/400 compilers, whereas NMI instructions are used by the Integrated Language Environment compilers. During

4740-535: The same executable and call procedures written in any of the other ILE languages. When PASE was introduced, it was necessary to compile code for PASE on an AIX system. This requirement was removed in OS/400 V5R2 when it became possible to compile code using the IBM XL compiler suite inside PASE itself. Since then, other compilers have been ported to PASE, including gcc . Certain development tools for IBM i run on top of

4819-445: The same time, i5/OS was renamed to IBM i , in order to remove the association with POWER5 processors. The two most recent versions of the operating system at that time, which had been released as i5/OS V5R4 and V6R1, were renamed to IBM i 5.4 and 6.1. Along with the rebranding to IBM i, IBM changed the versioning nomenclature for the operating system. Prior releases used a Version, Release, Modification scheme, e.g. V2R1M1. This

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4898-434: The standard 9370 hardware. Each DASD/Tape Controller had eight device addresses and provided a data transfer rate of 3 MB. IBM 9332 (368 MB) and IBM 9335 (824 MB) DASD and IBM 9347 nine-track half-inch tape have been announced for the 9370s. Each Workstation Controller could interface up to 32 IBM 3270 terminals / printers. Software for all models included VM/SP +VM/IS, VSE/SP , and VM/SP+ IX/370 , while MVS/SP

4977-727: The system with twinax cabling. With the decline of dedicated terminal hardware, modern IBM i systems are typically accessed through 5250 terminal emulators . IBM provides two terminal emulator products for IBM i: In addition, IBM provides a web-based management console and performance analysis product named IBM Navigator for i. Programming languages available from IBM for IBM i include RPG , Control Language , C , C++ , Java , EGL , COBOL , and REXX . Compilers were previously available for Pascal , BASIC , PL/I and Smalltalk but have since been discontinued. The Integrated Language Environment (ILE) allows programs from ILE compatible languages (C, C++, COBOL, RPG, and CL), to be bound into

5056-441: The underlying hardware. This isolation is more thorough than the hardware abstractions of other operating systems, and includes abstracting the instruction set architecture of the processor, the size of the address space and the specifics of I/O and persistence. This is accomplished through two interrelated mechanisms: The hardware isolation provided by the TIMI allowed IBM to replace the AS/400's 48-bit IMPI architecture with

5135-495: The very low end of, and compatible with System/370 . The media of the day, referring to the VAX systems manufactured by Digital Equipment Corporation (DEC), carried IBM's alleged "VAX Killer" phrase, albeit often skeptically. The IBM 9370 was created in the aftermath of the failed Fort Knox project, which attempted to consolidate all of IBM's midrange systems into a single IBM 801 -based hardware platform. The announcement described

5214-427: The virtual instructions are interpreted at run time , TIMI instructions are never interpreted. They constitute an intermediate compile time step and are translated into the processor's instruction set as the final compilation step. The TIMI instructions are stored within the final program object, in addition to the executable machine instructions. This is how application objects compiled on one processor family (e.g.,

5293-537: Was added in OS/400 V1R3 and become the default security level for the operating system. The addition of Level 40 required the removal of the capability addressing model of the System/38 which was also present in earlier releases of OS/400. Security level 50 was added in V2R3 when OS/400 was certified to TCSEC C2 security. IBM 9370 The IBM 9370 systems are "baby mainframe" midrange computers , released 1986 at

5372-584: Was based on technology created for the Fort Knox project - reusing some of the IBM 801 -based processor design, and the SPD I/O bus which was derived from the Series/1 bus. All models included a floating-point accelerator as well as a processor console to install, operate and maintain the system. A militarized variant of the 9370 named the System/MIL-370 was announced alongside the original 9370 models, designed to operate in harsher environmental conditions than

5451-404: Was described simply as "data base support". It was given the name DB2/400 in 1994 to indicate comparable functionality to IBM's other commercial databases. Despite the Db2 branding, Db2 for IBM i is an entirely separate codebase to Db2 on other platforms, and is tightly integrated into the SLIC layer of IBM i as opposed to being an optional product. IBM i provides two mechanisms for accessing

5530-492: Was essentially an evolution of the System/38 which reused some of the technology developed for the Fort Knox project. Silverlake's goal was to deliver a replacement for the System/36 and System/38 in as short of a timeframe as possible, as the Fort Knox project had stalled new product development at Rochester, leaving IBM without a competitive midrange system. On its launch in 1986, the System/370-compatible IBM 9370

5609-441: Was inevitable. These engineers developed code which allowed System/36 applications to run on top of the System/38, and when Fort Knox was cancelled, this skunkworks project evolved into an official project to replace both the System/36 and System/38 with a single new hardware platform. The project became known as Silverlake (named for Silver Lake in Rochester, Minnesota ) and officially began in December 1985. The Silverlake hardware

5688-793: Was named Operating System/400 (OS/400). The creators of the AS/400 originally planned to use the name System/40 , but IBM had adopted a new product nomenclature around the same time, which led to the Application System/400 name. Firstly, IBM began prefixing "System" in product names with words to indicate the intended use or target market of the system (e.g. Personal System/2 and Enterprise System/9000 ). Secondly, IBM decided to reserve one and two digit model numbers for personal systems (e.g. PS/2 and PS/55 ), three digit numbers for midrange systems (e.g. AS/400) and four digit numbers for mainframes (e.g. ES/9000 ). The reassignment of two digit model numbers from midrange systems to personal systems

5767-471: Was only available for larger models. An upgrade ( Miscellaneous Equipment Specification , MES) was available which involved - among other things - replacing the 9332 FBA drives with CKD enabled DASDs. In 1988, Distributed Processing Programming Executive DPPX/370 for ES/9370 was made available to customers wanting to migrate from the IBM 8100 running DPPX. The "Micro Channel 370" Models 010, 012, 014 (later 110, 112, 114) ES/9371 introduced in 1990 used

5846-611: Was positioned as IBM's preferred midrange platform, but failed to achieve the commercial success IBM hoped it would have. Much like Silverlake, the 9370 also reused the co-processor developed during the Fort Knox project as its main processor, and the same SPD I/O bus which was derived from the Series/1 bus. On June 21, 1988, IBM officially announced the Silverlake system as the Application System/400 (AS/400). The announcement included more than 1,000 software packages written for it by IBM and IBM Business Partners. The AS/400 operating system

5925-479: Was renamed as IBM i , in order to remove the association with POWER5 processors. IBM i is sold as one of the operating system options for Power Systems (along with AIX and Linux) instead of being tied to its own hardware platform. Although announced in 1988, the AS/400 remains IBM's most recent major architectural shift that was developed wholly internally. After the departure of CEO John Akers in 1993, when IBM looked likely to be split up, Bill Gates commented that

6004-538: Was renamed to i5/OS in 2004, before being renamed a second time to IBM i in 2008. It is an evolution of the System/38 CPF operating system, with compatibility layers for System/36 SSP and AIX applications. It inherits a number of distinctive features from the System/38 platform, including the Machine Interface which provides hardware independence, the implementation of object-based addressing on top of

6083-521: Was replaced with a Version.Release scheme, e.g. 6.1. Beginning with IBM i 7.1, IBM replaced the Modification releases with Technology Refreshes . Technology Refreshes are delivered as optional PTFs for specific releases of the operating system which add new functionality or hardware support to the operating system. When IBM i was first released as OS/400, it was split into two layers, the hardware-dependent System Licensed Internal Code (SLIC) and

6162-459: Was the original design feature of the System/38 (S/38) in the mid 1970s planning for future use of faster processors, memory and an expanded address space. The original AS/400 CISC models used the same 48-bit address space as the S/38. The address space was expanded in 1995 when the RISC PowerPC RS64 64-bit CPU processor replaced the 48-bit CISC processor. OS/400 (now known as IBM i) is

6241-453: Was to prevent the personal systems from running out of single-digit numbers for new products. In 1990, IBM Rochester began work to replace the AS/400's original System/38-derived 48-bit CISC processors with a 96-bit architecture known as C-RISC (Commercial RISC ). Rather than being a clean-slate design, C-RISC would have added RISC-style and VLIW -style instructions to the AS/400's processor, while maintaining backwards compatibility with

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