How is Performance of CPU Measured

PERFORMANCE OF CPU

The performance a CPU is measured in terms of its data processing speed. Data processing speed of CPU depends upon the following three factors.

(1)Register Size

A large size register can hold larger amount of data. It increases the processing and accessing speed of CPU.

(2)Instruction Set Size

Every processor can execute a fixed set instruction for arithmetic and logical operations. It is called the instruction set of the CPU. Different CPUs have different instruction sets. Usually a modern CPUs instruction set consists of 80 to 120 instructions. Larger instruction set of CPU increases data processing speed.

(3)Clock Speed

Processing speed of the CPU depends upon the clock speed of the computer. Usually 1 to 6 ticks of the clock are required to perform one instruction. Clock speed usually varies from 100  MHz to 1000 MHz. Higher clock speed means faster data processing by the CPU.

ADVANCED FEATURES

Modern CPUs have certain advanced features that increase their data processing speed. These features are:

(1)Cache Memory

A cache (pronounced as cash) is a small very memory within the CPU. It is for speeding up the internal data transfer.

(2)Math Coprocessor

Math coprocessor is a special circuitry specially designed to perform larger and complex mathematical calculations. These are used to increase the performance of the CPU while running application program that need complicated computations. Until recently math coprocessors were used as separate chips that could be added to the computer system. Nowadays these are built within the CPU.

(3)Stack Register & Stack Management Instruction

A stack is a set of blocks of memory location where a series of data is stored one upon the other. The data cannot be stored and retrieved randomly. It is stored and retrieved in some order. The data stored in the last position is retrieved first. This method of storing and retrieving data is called Last In First Out (LIFO).