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Cold Data
In computer storage, cold data refers to data that is rarely accessed, therefore considered "cold". Cold data is the opposite of hot data, which is data that is frequently accessed. To optimize storage costs, cold data can be stored on lower performing and less expensive storage media. For example, solid state disks may be used for storing hot data, while cold data can be moved to hard drives, optical discs, tapes or migrated to cloud storage. Enterprise Storage Forum See also * * |
Computer Storage
Computer data storage is a technology consisting of computer components and recording media that are used to retain digital data. It is a core function and fundamental component of computers. The central processing unit (CPU) of a computer is what manipulates data by performing computations. In practice, almost all computers use a storage hierarchy, which puts fast but expensive and small storage options close to the CPU and slower but less expensive and larger options further away. Generally, the fast volatile technologies (which lose data when off power) are referred to as "memory", while slower persistent technologies are referred to as "storage". Even the first computer designs, Charles Babbage's Analytical Engine and Percy Ludgate's Analytical Machine, clearly distinguished between processing and memory (Babbage stored numbers as rotations of gears, while Ludgate stored numbers as displacements of rods in shuttles). This distinction was extended in the Von Neumann a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid State Disks
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is also sometimes called a semiconductor storage device, a solid-state device or a solid-state disk, even though SSDs lack the physical spinning disks and movable read–write heads used in hard disk drives (HDDs) and floppy disks. SSD also has rich internal parallelism for data processing. In comparison to hard disk drives and similar electromechanical media which use moving parts, SSDs are typically more resistant to physical shock, run silently, and have higher input/output rates and lower latency. SSDs store data in semiconductor cells. cells can contain between 1 and 4 bits of data. SSD storage devices vary in their properties according to the number of bits stored in each cell, with single-bit cells ("Single Level Cells" or "SLC") ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hard Drives
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is accessed in a random-access manner, meaning that individual blocks of data can be stored and retrieved in any order. HDDs are a type of non-volatile storage, retaining stored data when powered off. Modern HDDs are typically in the form of a small rectangular box. Introduced by IBM in 1956, HDDs were the dominant secondary storage device for general-purpose computers beginning in the early 1960s. HDDs maintained this position into the modern era of servers and personal computers, though personal computing devices produced in large volume, like cell phones and tablets, rely on fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Disc
In computing and optical disc recording technologies, an optical disc (OD) is a flat, usually circular disc that encodes binary data (bits) in the form of pits and lands on a special material, often aluminum, on one of its flat surfaces. Its main uses are physical offline data distribution and long-term archival. Changes from pit to land or from land to pit correspond to a binary value of 1; while no change, regardless of whether in a land or a pit area, corresponds to a binary value of 0. Non-circular optical discs exist for fashion purposes; see shaped compact disc. Design and technology The encoding material sits atop a thicker substrate (usually polycarbonate) that makes up the bulk of the disc and forms a dust defocusing layer. The encoding pattern follows a continuous, spiral path covering the entire disc surface and extending from the innermost track to the outermost track. The data are stored on the disc with a laser or stamping machine, and can be accesse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Tape-Open
Linearity is the property of a mathematical relationship (''function Function or functionality may refer to: Computing * Function key, a type of key on computer keyboards * Function model, a structured representation of processes in a system * Function object or functor or functionoid, a concept of object-oriente ...'') that can be graphically represented as a straight line. Linearity is closely related to ''Proportionality (mathematics), proportionality''. Examples in physics include rectilinear motion, the linear relationship of voltage and Electric current, current in an electrical conductor (Ohm's law), and the relationship of mass and weight. By contrast, more complicated relationships are ''nonlinear''. Generalized for functions in more than one dimension (mathematics), dimension, linearity means the property of a function of being compatible with addition and scale analysis (mathematics), scaling, also known as the superposition principle. The word linear comes fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloud Storage
Cloud storage is a model of computer data storage in which the digital data is stored in logical pools, said to be on "the cloud". The physical storage spans multiple servers (sometimes in multiple locations), and the physical environment is typically owned and managed by a hosting company. These cloud storage providers are responsible for keeping the data available and accessible, and the physical environment secured, protected, and running. People and organizations buy or lease storage capacity from the providers to store user, organization, or application data. Cloud storage services may be accessed through a colocated cloud computing service, a web service application programming interface (API) or by applications that use the API, such as cloud desktop storage, a cloud storage gateway or Web-based content management systems. History Cloud computing is believed to have been invented by Joseph Carl Robnett Licklider in the 1960s with his work on ARPANET to connect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hierarchical Storage Management
Hierarchical storage management (HSM), also known as Tiered storage, is a data storage and Data management technique that automatically moves data between high-cost and low-cost storage media. HSM systems exist because high-speed storage devices, such as solid state drive arrays, are more expensive (per byte stored) than slower devices, such as hard disk drives, optical discs and magnetic tape drives. While it would be ideal to have all data available on high-speed devices all the time, this is prohibitively expensive for many organizations. Instead, HSM systems store the bulk of the enterprise's data on slower devices, and then copy data to faster disk drives when needed. The HSM system monitors the way data is used and makes best guesses as to which data can safely be moved to slower devices and which data should stay on the fast devices. HSM may also be used where more robust storage is available for long-term archiving, but this is slow to access. This may be as simple as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache (computing)
In computing, a cache ( ) is a hardware or software component that stores data so that future requests for that data can be served faster; the data stored in a cache might be the result of an earlier computation or a copy of data stored elsewhere. A ''cache hit'' occurs when the requested data can be found in a cache, while a ''cache miss'' occurs when it cannot. Cache hits are served by reading data from the cache, which is faster than recomputing a result or reading from a slower data store; thus, the more requests that can be served from the cache, the faster the system performs. To be cost-effective and to enable efficient use of data, caches must be relatively small. Nevertheless, caches have proven themselves in many areas of computing, because typical computer applications access data with a high degree of locality of reference. Such access patterns exhibit temporal locality, where data is requested that has been recently requested already, and spatial locality, where d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sneakernet
Sneakernet, also called sneaker net, is an informal term for the transfer of electronic information by physically moving media such as magnetic tape, floppy disks, optical discs, USB flash drives or external hard drives between computers, rather than transmitting it over a computer network. The term, a tongue-in-cheek play on ''net(work)'' as in ''Internet'' or ''Ethernet'', refers to walking in sneakers as the transport mechanism. Alternative terms may be floppy net, train net, or pigeon net. Summary and background Sneakernets are in use throughout the computer world. A sneakernet may be used when computer networks are prohibitively expensive for the owner to maintain; in high-security environments where manual inspection (for re-classification of information) is necessary; where information needs to be shared between networks with different levels of security clearance; when data transfer is impractical due to bandwidth limitations; when a particular system is simply incompa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Storage
Data storage is the recording (storing) of information (data) in a storage medium. Handwriting, phonographic recording, magnetic tape, and optical discs are all examples of storage media. Biological molecules such as RNA and DNA are considered by some as data storage. Recording may be accomplished with virtually any form of energy. Electronic data storage requires electrical power to store and retrieve data. Data storage in a digital, machine-readable medium is sometimes called ''digital data''. Computer data storage is one of the core functions of a general-purpose computer. Electronic documents can be stored in much less space than paper documents. Barcodes and magnetic ink character recognition (MICR) are two ways of recording machine-readable data on paper. Recording media A recording medium is a physical material that holds information. Newly created information is distributed and can be stored in four storage media–print, film, magnetic, and optical–and seen or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
