Computer system architecture 64 bits#
Computer system architecture software#
Computer system architecture series#

Programs and data are kept in auxiliary memory when not in immediate use, so that auxiliary memory is essentially a long-term storage medium. This is achieved by placing the contents of the large, “virtual” memory on a large but slow auxiliary storage device, and bringing portions of it into main memory, as required by the programs, in a way that is transparent to the programmer.Īuxiliary memory (sometimes called secondary storage) is the slowest, lowest-cost, and highest-capacity computer storage area.

Virtual memory is a technique whereby the programmer is given the illusion of a very large main memory, when in fact it has only a modest size. With cacheing, a small, fast memory system contains the most frequently used words from a slower, larger main memory. Interleaving involves the use of two or more independent memory systems, combined in a way that makes them appear to be a single, faster system. Two prevalent techniques for increasing effective speed are interleaving and cacheing, while virtual memory is a popular way to increase the effective size. A major goal of the computer architect is to increase the effective speed and size of a memory system without incurring a large cost penalty. Main memory holds the data to be processed and the instructions that specify what processing is to be done. Normally contained within the processing unit, registers hold data that are involved with the computation currently being performed. Registers are the fastest and most costly storage units in a computer. These types include registers, main memory, and secondary or auxiliary storage. A computer will generally have several different kinds of storage devices, each organized to hold one or more words of data.

Computer system architecture 64 bits#

Bits are conceptually combined into larger units called bytes (usually 8 bits each) and words (usually 8 to 64 bits each).

Computer system architecture series#

In a digital computer, these are stored in a form known as binary, which means that each datum or instruction is represented by a series of bits. The storage or memory of a computer system holds the data that the computer will process and the instructions that indicate what processing is to be done. The storage system is used to keep data and programs the processor is the unit that controls the operation of the system and carries out various computations the peripheral devices are used to communicate with the outside world and the input/output system allows the previous components to communicate with one another. Over the years, other goals have been added, such as making it easier to run multiple programs concurrently or improving the performance of programs written in higher-level languages.Ī computer system consists of four major components (see illustration): storage, processor, peripherals, and input/output (communication). The architect's main goal has long been to produce a computer that is as fast as possible, within a given set of cost constraints.

Computer system architecture software#

Architecture consists of those characteristics which affect the design and development of software programs, whereas implementation focuses on those characteristics which determine the relative cost and performance of the system. It is related to, but different from, computer implementation.

It is analogous to the architecture of a building, determining the overall organization, the attributes of the component parts, and how these parts are combined. The discipline that defines the conceptual structure and functional behavior of a computer system. McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.