|
IBM Parallel Sysplex
In computing, a Parallel Sysplex is a computer cluster, cluster of IBM mainframes acting together as a single system image with z/OS. Used for disaster recovery, Parallel Sysplex combines data sharing and parallel computing to allow a cluster of up to 32 systems to share a workload for high performance computing, high performance and high availability. Sysplex In 1990, IBM mainframe computers introduced the concept of a Systems Complex, commonly called a Sysplex, with MVS/ESA SPV4.1. This allows authorized components in up to eight logical partitions (LPARs) to communicate and cooperate with each other using the IBM XCF, XCF protocol. Components of a Sysplex include: * A common time source to synchronize all member systems' clocks. This can involve either a Sysplex timer (Model 9037), or the Server Time Protocol (STP) * Global Resource Serialization (GRS), which allows multiple systems to access the same resources concurrently, serializing where necessary to ensure exclusive ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Cluster
A computer cluster is a set of computers that work together so that they can be viewed as a single system. Unlike grid computers, computer clusters have each node set to perform the same task, controlled and scheduled by software. The newest manifestation of cluster computing is cloud computing. The components of a cluster are usually connected to each other through fast local area networks, with each node (computer used as a server) running its own instance of an operating system. In most circumstances, all of the nodes use the same hardware and the same operating system, although in some setups (e.g. using Open Source Cluster Application Resources (OSCAR)), different operating systems can be used on each computer, or different hardware. Clusters are usually deployed to improve performance and availability over that of a single computer, while typically being much more cost-effective than single computers of comparable speed or availability. Computer clusters emerged as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coupling Facility
In IBM System/390 and IBM Z mainframe computers, a Coupling Facility or CF is a piece of computer hardware or virtual machine that coordinates multiple processors. A Parallel Sysplex relies on one or more Coupling Facilities (CFs). A coupling facility is a mainframe processor (runs in an own LPAR, with dedicated physical CP, defined through Hardware Management Console (HMC)), with memory and special channels (CF Links), and a specialized operating system called Coupling Facility Control Code (CFCC). It has no I/O devices, other than the CF links. The information in the CF resides entirely in memory as CFCC is not a virtual memory operating system. A CF typically has a large memory – of the order of several tens of gigabytes. The CF runs no application software. When originally introduced, the CFCC executed in a separate 9674 mainframe unit that was essentially a processor without I/O facilities other than the CF links. Later IBM enabled the use of an Internal Coupling Fac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-availability Cluster Computing
High availability (HA) is a characteristic of a system that aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period. There is now more dependence on these systems as a result of modernization. For example, to carry out their regular daily tasks, hospitals and data centers need their systems to be highly available. Availability refers to the ability of the user to access a service or system, whether to submit new work, update or modify existing work, or retrieve the results of previous work. If a user cannot access the system, it is considered ''unavailable from the user's perspective''. The term ''downtime'' is generally used to refer to describe periods when a system is unavailable. Resilience High availability is a property of network resilience, the ability to "provide and maintain an acceptable level of service in the face of faults and challenges to normal operation." Threats and challenges for services can range from si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM Mainframe Technology
International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is a publicly traded company and one of the 30 companies in the Dow Jones Industrial Average. IBM is the largest industrial research organization in the world, with 19 research facilities across a dozen countries; for 29 consecutive years, from 1993 to 2021, it held the record for most annual U.S. patents generated by a business. IBM was founded in 1911 as the Computing-Tabulating-Recording Company (CTR), a holding company of manufacturers of record-keeping and measuring systems. It was renamed "International Business Machines" in 1924 and soon became the leading manufacturer of punch-card tabulating systems. During the 1960s and 1970s, the IBM mainframe, exemplified by the System/360 and its successors, was the world's dominant computing platform, with the company p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LPAR
A logical partition (LPAR) is a subset of a computer's hardware resources, virtualized as a separate computer. In effect, a physical machine can be partitioned into multiple logical partitions, each hosting a separate instance of an operating system. History IBM developed the concept of hypervisors (virtual machines in CP-40 and CP-67) and in 1972 provided it for the S/370 as Virtual Machine Facility/370. IBM introduced the Start Interpretive Execution (SIE) instruction (designed specifically for the execution of virtual machines) in 1983 as part of 370-XA architecture on the IBM 3081, as well as VM/XA versions of VM to exploit it. Amdahl Corporation's Multiple Domain Facility (MDF) was introduced in 1982. IBM introduced its functionally similar PR/SM in 1988, implemented on its ESA/370 architecture released that year with the IBM 3090 processors. PR/SM (Processor Resource/System Manager) is a type-1 Hypervisor (a virtual machine monitor) that allows multiple logica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
System Z
IBM Z is a family name used by IBM for all of its z/Architecture mainframe computers. In July 2017, with another generation of products, the official family was changed to IBM Z from IBM z Systems; the IBM Z family will soon include the newest model, the IBM z17, as well as the z16, z15, z14, and z13 (released under the IBM z Systems/IBM System z names), the IBM zEnterprise models (in common use the zEC12 and z196), the IBM System z10 models (in common use the z10 EC), the IBM System z9 models (in common use the z9EC) and ''IBM eServer zSeries'' models (in common use refers only to the z900 and z990 generations of mainframe). Architecture The ''zSeries,'' ''zEnterprise,'' ''System z'' and ''IBM Z'' families were named for their availability – ''z'' stands for zero downtime. The systems are built with spare components capable of hot failovers to ensure continuous operations. The IBM Z family maintains full backward compatibility. In effect, current systems are the direct, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM Global Mirror
Global Mirror is an IBM technology that provides data replication over extended distances between two sites for business continuity and disaster recovery. If adequate bandwidth exists, Global Mirror provides a recovery point objective (RPO) of as low as 3–5 seconds between the two sites at extended distances with no performance impact on the application at the primary site. It replicates the data asynchronously and also forms a consistency group at a regular interval allowing a clean recovery of the application. The two sites can be on separate continents or simply on different utility grids. IBM also provides a synchronous data replication called Metro Mirror, which is designed to support replication at "Metropolitan" distances of (normally) less than 300 km. Global Mirror is based on IBM Copy Services functions: Global Copy and FlashCopy. Global mirror periodically pauses updates of the primary volumes and swaps change recording bitmaps. It then uses the previous b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extended Remote Copy
Extended Remote Copy or XRC is an IBM zSeries and System z9 mainframe computer technology for data replication. It combines supported hardware and z/OS software to provide asynchronous replication over long distances. It is complementary to IBM's Peer to Peer Remote Copy (PPRC) service, which is designed to operate either synchronously or asynchronously over shorter distances. XRC as a z/OS copy services solution can be compared to Global Mirror for ESS, which is a controller-based solution for either the open systems or z/Series environments. Both Global Mirror for ESS (Asynchronous PPRC) and XRC (Global Mirror for z/Series) are asynchronous replication technologies, although their implementations are somewhat different. Extended Remote Copy or XRC is now known as Global Mirror for z/Series (XRC). XRC is a z/Series asynchronous disk mirroring technique which is effective over any distance. It keeps the data time consistent across multiple ESS (Enterprise Storage Server) or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peer To Peer Remote Copy
Peer to Peer Remote Copy or PPRC is a protocol to storage replication, replicate a storage volume to another control unit at a remote site. Synchronous replication, Synchronous PPRC causes each write to the primary storage volume to be performed to the secondary volume as well, and the I/O is only considered complete when the update to both the primary and secondary volumes has completed. Asynchronous PPRC will flag tracks on the primary to be duplicated to the secondary when time permits. PPRC is also the name IBM calls their implementation of the protocol for their storage hardware. Other vendors have their own implementation. For example, the HDS implementation is called TrueCopy. EMC also provides a similar capability on their VPLEX platforms called "MirrorView". PPRC can be used to provide very fast data recovery due to failure of the primary site. In IBM zSeries computers with two direct access storage device (DASD) control units connected through dedicated connections, PPRC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
System Z9
IBM System z9 is a line of IBM mainframe computers. The first models were available on September 16, 2005. The System z9 also marks the end of the previously used eServer zSeries naming convention. It was also the last mainframe computer that NASA ever used. Background System z9 is a mainframe using the z/Architecture, previously known as ESAME. z/Architecture is a 64-bit architecture which replaces the previous 31-bit-addressing/32-bit-data ESA/390 architecture while remaining completely compatible with it as well as the older 24-bit-addressing/32-bit-data System/360 architecture. The primary advantage of this arrangement is that memory intensive applications like DB2 are no longer bounded by 31-bit memory restrictions while older applications can run without modifications. Name change With the announcement of the System z9 Business Class server, IBM has renamed the System z9 109 as the System z9 Enterprise Class server. IBM documentation abbreviates them as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middleware
Middleware is a type of computer software program that provides services to software applications beyond those available from the operating system. It can be described as "software glue". Middleware makes it easier for software developers to implement communication and input/output, so they can focus on the specific purpose of their application. It gained popularity in the 1980s as a solution to the problem of how to link newer applications to older legacy systems, although the term had been in use since 1968. In distributed applications The term is most commonly used for software that enables communication and management of data in distributed applications. An IETF workshop in 2000 defined middleware as "those services found above the transport (i.e. over TCP/IP) layer set of services but below the application environment" (i.e. below application-level APIs). In this more specific sense ''middleware'' can be described as the hyphen ("-") in '' client-server'', or the ''-to-'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating System
An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for efficient use of the system and may also include accounting software for cost allocation of Scheduling (computing), processor time, mass storage, peripherals, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computerfrom cellular phones and video game consoles to web servers and supercomputers. , Android (operating system), Android is the most popular operating system with a 46% market share, followed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
