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LESSON 4

COMPUTER PERFORMANCE

PART 1

Task1. Learn the following words and word combinations:
Efficiency, applicable measurement, multicore and vector processing
CPU, misleading, move away, clock speed, likelihood, latency,
throughput, interrupt latency.

Task 2. Make up your own sentences using words and phrases
from the previous exercise.

TEXT 1
COMPUTER PERFORMANCE EARLIER AND NOWADAYS
Modern computer performance is often described in MIPS per
MHz (millions of instructions per second per millions of cycles per
second of clock speed). This measures the efficiency of the
architecture at any clock speed. Since a faster clock can make a faster
computer, this is a useful, widely applicable measurement. Historic
computers had MIPs/MHz as low as 0.1 Simple modern processors
easily reach near 1. Superscalar processors may reach three to five by
executing several instructions per clock cycle. Multicore and vector
processing CPUs can multiply this further by acting on a lot of data
per instruction, with have several CPUs executing in parallel.
Counting machine language instructions would be misleading
because they can do varying amounts of work in different ISAs. The
"instruction" in the standard measurements is not a count of the ISA's
actual machine language instructions, but a historical unit of
measurement, usually based on the speed of the VAX computer
architecture.
Historically, many people measured a computer's speed by the
clock rate (usually in MHz or GHz). This refers to the cycles per

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