Operating Speed

Operating Speed 

(digital computers), the average statistical number of operations (except operations of input, output, and access to files) performed by a computer per unit of time (nominal speed); one of the basic parameters of a digital computer that characterizes its performance. For example, the average speed of the Ural-11 digital computer is 50,000 operations per second; the BESM-6, which is designed to solve a broad range of complex problems in science, engineering, and the national economy, works at 1 million operations per second. The operating speed, taking account of the average time expenditures for input, output, exchange of information with files, and the monitoring of the computer’s operation, is called the effective speed.

The effective speed (V_e) is related to the nominal speed (V_n), by the formula V_e = vV_n, where v is a certain generalized coefficient that takes into account the influence of low-speed devices, the logic structure of the computer, characteristics of the instruction repertoire, the influence of computer reliability, and losses owing to monitoring procedures and diagnostic-repair activities. As a rule, the value of this coefficient depends on the type of problem, each of which has its own corresponding V_e.

Operating speed is sometimes defined as the number of “addition” or “multiplication” operations. For example, the VNIIEM-3 control digital computer performs these operations with a speed of 40,000 and 16,000 operations per second respectively. In addition to the methods cited, there is also a method for evaluating computer speed by the number of typical problems the computer solves per unit time.

I. A. DANIL’CHENKO