|
Memory Architecture
Memory architecture describes the methods used to implement electronic computer data storage in a manner that is a combination of the fastest, most reliable, most durable, and least expensive way to store and retrieve information. Depending on the specific application, a compromise of one of these requirements may be necessary in order to improve another requirement. Memory architecture also explains how binary digits are converted into electric signals and then stored in the memory cells. And also the structure of a memory cell. For example, dynamic memory is commonly used for primary data storage due to its fast access speed. However dynamic memory must be repeatedly refreshed with a surge of current dozens of time per second, or the stored data will decay and be lost. Flash memory allows for long-term storage over a period of years, but it is much slower than dynamic memory, and the static memory storage cells wear out with frequent use. Similarly, the data bus is often designe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamic Memory
Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. This is critical to any advanced computer system where more than a single process might be underway at any time. Several methods have been devised that increase the effectiveness of memory management. Virtual memory systems separate the memory addresses used by a process from actual physical addresses, allowing separation of processes and increasing the size of the virtual address space beyond the available amount of RAM using paging or swapping to secondary storage. The quality of the virtual memory manager can have an extensive effect on overall system performance. In some operating systems, e.g. OS/360 and successors, memory is managed by the operating system. In other operating systems, e.g. Unix-like operating syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
64-bit
In computer architecture, 64-bit Integer (computer science), integers, memory addresses, or other Data (computing), data units are those that are 64 bits wide. Also, 64-bit central processing unit, CPUs and arithmetic logic unit, ALUs are those that are based on processor registers, address buses, or Bus (computing), data buses of that size. A computer that uses such a processor is a 64-bit computer. From the software perspective, 64-bit computing means the use of machine code with 64-bit virtual memory addresses. However, not all 64-bit instruction sets support full 64-bit virtual memory addresses; x86-64 and ARMv8, for example, support only 48 bits of virtual address, with the remaining 16 bits of the virtual address required to be all 0's or all 1's, and several 64-bit instruction sets support fewer than 64 bits of physical memory address. The term ''64-bit'' also describes a generation of computers in which 64-bit processors are the norm. 64 bits is a Word (computer archit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lernmatrix
Lernmatrix, an associative-memory-like architecture of an artificial neural network, invented around 1960 by Karl Steinbuch Karl W. Steinbuch (June 15, 1917 in Stuttgart-Bad Cannstatt – June 4, 2005 in Ettlingen) was a German computer scientist, cyberneticist, and electrical engineer. He was an early and influential researcher of German computer science, and was .... External links A new theoretical framework for the Steinbuch's Lernmatrix [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Memory Area
In DOS memory management, the high memory area (HMA) is the RAM area consisting of the first 65520 bytes above the one megabyte in an IBM AT or compatible computer. In real mode, the segmentation architecture of the Intel 8086 and subsequent processors identifies memory locations with a 16-bit segment and a 16-bit offset, which is resolved into a physical address via (segment) × 16 + (offset). Although intended to address only 1 Megabyte (MB) (220 bytes) of memory, segment:offset addresses at FFFF:0010 and beyond reference memory beyond 1 MB (FFFF0 + 0010 = 100000). So, on an 80286 and subsequent processors, this mode can actually address the first 65520 bytes of extended memory as part of the 64 KB range starting 16 bytes before the 1 MB mark—FFFF:0000 (0xFFFF0) to FFFF:FFFF (0x10FFEF). The Intel 8086 and 8088 processors, with only 1 MB of memory and only 20 address lines, wrapped around at the 20th bit, so that address FFFF:0010 w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flat Memory Model
Flat memory model or linear memory model refers to a memory addressing paradigm in which "memory appears to the program as a single contiguous address space." The CPU can directly (and linearly) address all of the available memory locations without having to resort to any sort of memory segmentation or paging schemes. Memory management and address translation can still be implemented ''on top of'' a flat memory model in order to facilitate the operating system's functionality, resource protection, multitasking or to increase the memory capacity beyond the limits imposed by the processor's physical address space, but the key feature of a flat memory model is that the entire memory space is linear, sequential and contiguous. In a simple controller, or in a ''single tasking'' embedded application, where memory management is not needed nor desirable, the flat memory model is the most appropriate, because it provides the simplest interface from the programmer's point of view, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extended Memory
In DOS memory management, extended memory refers to memory above the first megabyte (220 bytes) of address space in an IBM PC or compatible with an 80286 or later processor. The term is mainly used under the DOS and Windows operating systems. DOS programs, running in real mode or virtual x86 mode, cannot directly access this memory, but are able to do so through an application programming interface called the ''Extended Memory Specification'' (XMS). This API is implemented by a driver (such as HIMEM.SYS) or the operating system, which takes care of memory management and copying memory between conventional and extended memory, by temporarily switching the processor into protected mode. In this context, the term "extended memory" may refer to either the whole of the extended memory or only the portion available through this API. Extended memory can also be accessed directly by DOS programs running in protected mode using VCPI or DPMI, two (different and incompatible) methods of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expanded Memory
In DOS memory management, expanded memory is a system of bank switching that provided additional memory to DOS programs beyond the limit of conventional memory (640 KiB). ''Expanded memory'' is an umbrella term for several incompatible technology variants. The most widely used variant was the Expanded Memory Specification (EMS), which was developed jointly by Lotus Software, Intel, and Microsoft, so that this specification was sometimes referred to as "LIM EMS". LIM EMS had several versions. The first widely implemented version was EMS 3.2, which supported up to 8 MiB of expanded memory and uses parts of the address space normally dedicated to communication with peripherals (upper memory) to map portions of the expanded memory. EEMS, an expanded-memory management standard competing with LIM EMS 3.x, was developed by AST Research, Quadram and Ashton-Tate ("AQA"); it could map any area of the lower 1 MiB. EEMS ultimately was incorporated in LIM EMS 4.0, which supporte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual-channel Architecture
In the fields of digital electronics and computer hardware, multi-channel memory architecture is a technology that increases the data transfer rate between the DRAM memory and the memory controller by adding more channels of communication between them. Theoretically, this multiplies the data rate by exactly the number of channels present. Dual-channel memory employs two channels. The technique goes back as far as the 1960s having been used in IBM System/360 Model 91 and in CDC 6600. Modern high-end desktop and workstation processors such as the AMD Ryzen Threadripper series and the Intel Core i9 Extreme Edition lineup support quad-channel memory. Server processors from the AMD Epyc series and the Intel Xeon platforms give support to memory bandwidth starting from quad-channel module layout to up to octa-channel layout. In March 2010, AMD released Socket G34 and Magny-Cours Opteron 6100 series processors with support for quad-channel memory. In 2006, Intel released chipsets that s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Shared Memory
In computer science, distributed shared memory (DSM) is a form of memory architecture where physically separated memories can be addressed as a single shared address space. The term "shared" does not mean that there is a single centralized memory, but that the address space is shared—i.e., the same physical address on two processors refers to the same location in memory. Distributed global address space (DGAS), is a similar term for a wide class of software and hardware implementations, in which each node of a cluster has access to shared memory in addition to each node's private (i.e., not shared) memory. Overview A distributed-memory system, often called a multicomputer, consists of multiple independent processing nodes with local memory modules which is connected by a general interconnection network. Software DSM systems can be implemented in an operating system, or as a programming library and can be thought of as extensions of the underlying virtual memory architecture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Memory
In computer science, distributed memory refers to a multiprocessor computer system in which each processor has its own private memory. Computational tasks can only operate on local data, and if remote data are required, the computational task must communicate with one or more remote processors. In contrast, a shared memory multiprocessor offers a single memory space used by all processors. Processors do not have to be aware where data resides, except that there may be performance penalties, and that race conditions are to be avoided. In a distributed memory system there is typically a processor, a memory, and some form of interconnection that allows programs on each processor to interact with each other. The interconnect can be organised with point to point links or separate hardware can provide a switching network. The network topology is a key factor in determining how the multiprocessor machine scales. The links between nodes can be implemented using some standard network pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deterministic Memory
In computing, deterministic memory is computer memory which contains values that can be depended on from access to access. The term is also used in conjunction with achieving real-time functionality, especially in conjunction with embedded processor applications. See also * Embedded system * Memory management * Real-time computing Real-time computing (RTC) is the computer science term for hardware and software systems subject to a "real-time constraint", for example from event to system response. Real-time programs must guarantee response within specified time constrai ... External links Design Patterns for Real-Time Computer Music Systems* ttps://archive.today/20130121165928/http://www.dspdesignline.com/191502939;jsessionid=4B5SYWAIOJXTQQSNDLQSKICCJUNN2JVN?printableArticle=true Harnessing parallelism from video-processing DSPsMemory ManagementPersistency Made Easy Computer memory {{Compu-hardware-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conventional Memory
In DOS memory management, conventional memory, also called base memory, is the first 640 kilobytes of the memory on IBM PC or compatible systems. It is the read-write memory directly addressable by the processor for use by the operating system and application programs. As memory prices rapidly declined, this design decision became a limitation in the use of large memory capacities until the introduction of operating systems and processors that made it irrelevant. 640 KB barrier The 640 KB barrier is an architectural limitation of IBM PC compatible PCs. The Intel 8088 CPU, used in the original IBM PC, was able to address 1 MB (220 bytes), since the chip offered 20 address lines. In the design of the PC, the memory below 640 KB was for random-access memory on the motherboard or on expansion boards, and it was called the conventional memory area. The first memory segment (64 KB) of the conventional memory area is named lower memory or low memory area. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
