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Thin Provisioning
In computing, thin provisioning involves using virtualization technology to give the appearance of having more physical resources than are actually available. If a system always has enough resource to simultaneously support all of the virtualized resources, then it is not thin provisioned. The term thin provisioning is applied to disk layer in this article, but could refer to an allocation scheme for any resource. For example, real memory in a computer is typically thin-provisioned to running tasks with some form of address translation technology doing the virtualization. Each task acts as if it has real memory allocated. The sum of the allocated virtual memory assigned to tasks typically exceeds the total of real memory. The efficiency of thin or thick/fat provisioning is a function of the use case, not of the technology. Thick provisioning is typically more efficient when the amount of resource used very closely approximates to the amount of resource allocated. Thin provisio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computing
Computing is any goal-oriented activity requiring, benefiting from, or creating computer, computing machinery. It includes the study and experimentation of algorithmic processes, and the development of both computer hardware, hardware and software. Computing has scientific, engineering, mathematical, technological, and social aspects. Major computing disciplines include computer engineering, computer science, cybersecurity, data science, information systems, information technology, and software engineering. The term ''computing'' is also synonymous with counting and calculation, calculating. In earlier times, it was used in reference to the action performed by Mechanical computer, mechanical computing machines, and before that, to Computer (occupation), human computers. History The history of computing is longer than the history of computing hardware and includes the history of methods intended for pen and paper (or for chalk and slate) with or without the aid of tables. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid-state Drive
A solid-state drive (SSD) is a type of solid-state storage device that uses integrated circuits to store data persistently. It is sometimes called semiconductor storage device, solid-state device, or solid-state disk. SSDs rely on non-volatile memory, typically NAND flash, to store data in memory cells. The performance and endurance of SSDs vary depending on the number of bits stored per cell, ranging from high-performing single-level cells (SLC) to more affordable but slower quad-level cells (QLC). In addition to flash-based SSDs, other technologies such as 3D XPoint offer faster speeds and higher endurance through different data storage mechanisms. Unlike traditional hard disk drives (HDDs), SSDs have no moving parts, allowing them to deliver faster data access speeds, reduced latency, increased resistance to physical shock, lower power consumption, and silent operation. Often interfaced to a system in the same way as HDDs, SSDs are used in a variety of devices, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fractional-reserve Banking
Fractional-reserve banking is the system of banking in all countries worldwide, under which banks that take deposits from the public keep only part of their deposit liabilities in liquid assets as a reserve, typically lending the remainder to borrowers. Bank reserves are held as cash in the bank or as balances in the bank's account at the central bank. Fractional-reserve banking differs from the hypothetical alternative model, full-reserve banking, in which banks would keep all depositor funds on hand as reserves. The country's central bank may determine a minimum amount that banks must hold in reserves, called the "reserve requirement" or "reserve ratio". Most commercial banks hold more than this minimum amount as excess reserves. Some countries, e.g. the core Anglosphere countries of the United States, the United Kingdom, Canada, Australia, and New Zealand, and the three Scandinavian countries, do not impose reserve requirements at all. Bank deposits are usually of a rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Storage Virtualization
In computer science, storage virtualization is "the process of presenting a logical view of the physical storage resources to" a host computer system, "treating all storage media (hard disk, optical disk, tape, etc.) in the enterprise as a single pool of storage." A "storage system" is also known as a storage array, disk array, or ''filer''. Storage systems typically use special hardware and software along with disk drives in order to provide very fast and reliable storage for computing and data processing. Storage systems are complex, and may be thought of as a special purpose computer designed to provide storage capacity along with advanced data protection features. Disk drives are only one element within a storage system, along with hardware and special purpose embedded software within the system. Storage systems can provide either block accessed storage, or file accessed storage. Block access is typically delivered over Fibre Channel, iSCSI, SAS, FICON or other prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Storage Hypervisor
Software-defined storage (SDS) is a marketing term for computer data storage software for policy-based provisioning and management of data storage independent of the underlying hardware. Software-defined storage typically includes a form of storage virtualization to separate the storage hardware from the software that manages it. The software enabling a software-defined storage environment may also provide policy management for features such as data deduplication, replication, thin provisioning, snapshots, copy-on-write clones, tiering and backup. Software-defined storage (SDS) hardware may or may not also have abstraction, pooling, or automation software of its own. When implemented as software only in conjunction with commodity servers with internal disks, it may suggest software such as a virtual or global file system or distributed block storage. If it is software layered over sophisticated large storage arrays, it suggests software such as storage virtualization or storage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statistical Time Division Multiplexing
Statistical multiplexing is a type of digital communication link sharing, sometimes abbreviated as STDM. It is very similar to dynamic bandwidth allocation (DBA). In statistical multiplexing, a communication channel is divided into an arbitrary number of variable bitrate digital channels or data streams. The link sharing is adapted to the instantaneous traffic demands of the data streams that are transferred over each channel. This is an alternative to creating a fixed sharing of a link, such as in general time division multiplexing (TDM) and frequency division multiplexing (FDM). When performed correctly, statistical multiplexing can provide a link utilization improvement, called the ''statistical multiplexing gain''. Statistical multiplexing is facilitated through packet mode or packet-oriented communication, which among others is utilized in Packet switching, packet switched computer networks. Each stream (computing), stream is divided into Network packet, packets that normally a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logical Volume Manager (Linux)
In Linux, Logical Volume Manager (LVM) is a device mapper framework that provides logical volume management for the Linux kernel. Most modern Linux distributions are LVM-aware to the point of being able to have their root file systems on a logical volume. Heinz Mauelshagen wrote the original LVM code in 1998, when he was working at Sistina Software, taking its primary design guidelines from the HP-UX's volume manager. Uses LVM is used for the following purposes: * Creating single logical volumes of multiple physical volumes or entire hard disks (somewhat similar to RAID 0, but more similar to JBOD), allowing for dynamic volume resizing. * Managing large hard disk farms by allowing disks to be added and replaced without downtime or service disruption, in combination with hot swapping. * On small systems (like a desktop), instead of having to estimate at installation time how big a partition might need to be, LVM allows filesystems to be easily resized as needed. * Performing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bank Run
A bank run or run on the bank occurs when many Client (business), clients withdraw their money from a bank, because they believe Bank failure, the bank may fail in the near future. In other words, it is when, in a fractional-reserve banking system (where banks normally only keep a small proportion of their assets as cash), numerous customers withdraw cash from deposit accounts with a financial institution at the same time because they believe that the financial institution is, or might become, insolvency, insolvent. When they transfer funds to another institution, it may be characterized as a capital flight. As a bank run progresses, it may become a self-fulfilling prophecy: as more people withdraw cash, the likelihood of default increases, triggering further withdrawals. This can destabilize the bank to the point where it runs out of cash and thus faces sudden bankruptcy. To combat a bank run, a bank may acquire more cash from other banks or from the central bank, or limit the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reserve Requirement
Reserve requirements are central bank regulations that set the minimum amount that a commercial bank must hold in liquid assets. This minimum amount, commonly referred to as the Bank reserves, commercial bank's reserve, is generally determined by the central bank on the basis of a specified proportion of Deposit account, deposit liabilities of the bank. This rate is commonly referred to as the cash reserve ratio or shortened as reserve ratio. Though the definitions vary, the commercial bank's reserves normally consist of currency, cash held by the bank and stored physically in the bank vault (vault cash), plus the amount of the bank's balance in that bank's account with the central bank. A bank is at liberty to hold in reserve sums above this minimum requirement, commonly referred to as ''excess reserves''. In some areas such as the euro area and the UK, tightening of reserve requirements in the home country is found to be associated with higher lending by foreign branches. Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
StorageTek
Storage Technology Corporation (StorageTek or STK, earlier STC) was a data storage technology company headquartered in Louisville, Colorado. New products include data retention systems, which it calls "information lifecycle management" (ILM). Its remaining product line is now part of Oracle Corporation, and marketed as Oracle StorageTek, with a focus on tape backup equipment and software to manage storage systems. History In 1969 four former IBM engineers— Jesse Aweida, Juan Rodriguez, Thomas S. Kavanagh, and Zoltan Herger—founded the Storage Technology Corporation. The headquarters was in Louisville, Boulder County, Colorado. In the 1970s, StorageTek launched its Disk Products division. After a failed attempt to develop an IBM-compatible mainframe, and an optical disk product line, the company filed for Chapter 11 bankruptcy protection in 1984. Starting in 1987, new management invested in an automated tape library product line that "picked" tapes from a silo-like contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Server (computing)
A server is a computer that provides information to other computers called " clients" on a computer network. This architecture is called the client–server model. Servers can provide various functionalities, often called "services", such as sharing data or resources among multiple clients or performing computations for a client. A single server can serve multiple clients, and a single client can use multiple servers. A client process may run on the same device or may connect over a network to a server on a different device. Typical servers are database servers, file servers, mail servers, print servers, web servers, game servers, and application servers. Client–server systems are usually most frequently implemented by (and often identified with) the request–response model: a client sends a request to the server, which performs some action and sends a response back to the client, typically with a result or acknowledgment. Designating a computer as "server-class hardwa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virtualization Technology
x86 virtualization is the use of hardware-assisted virtualization capabilities on an x86/x86-64 CPU. In the late 1990s x86 virtualization was achieved by complex software techniques, necessary to compensate for the processor's lack of hardware-assisted virtualization capabilities while attaining reasonable performance. In 2005 and 2006, both Intel (VT-x) and AMD (AMD-V) introduced limited hardware virtualization support that allowed simpler virtualization software but offered very few speed benefits. Greater hardware support, which allowed substantial speed improvements, came with later processor models. Software-based virtualization The following discussion focuses only on virtualization of the x86 architecture protected mode. In protected mode the operating system kernel runs at a higher privilege such as ring 0, and applications at a lower privilege such as ring 3. In software-based virtualization, a host OS has direct access to hardware while the guest OSs have limited acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
