With more and more data structures developed, many users are shifting to computer roles
from pure data processing to information processing. A high degree of parallelism has
been found at these levels. As the accumulated knowledge bases expanded rapidly in
recent years, there grew a strong demand to use computers for knowledge processing.
Intelligence is very difficult to create; its processing even more so. Todays computers are
very fast and obedient and have many reliable memory cells to be qualified for datainformation-knowledge processing.
Parallel processing is emerging as one of the key technology in area of modern
computers. Parallel appears in various forms such as lookahead, vectorization
concurrency, simultaneity, data parallelism, interleaving, overlapping, multiplicity,
replication, multiprogramming, multithreading and distributed computing at different
1.2 The state of computing
Modern computers are equipped with powerful hardware technology at the same time
loaded with sophisticated software packages. To access the art of computing we firstly
review the history of computers then study the attributes used for analysis of performance
Evolution of computer system
Presently the technology involved in designing of its hardware components of computers
and its overall architecture is changing very rapidly for example: processor clock rate
increase about 20% a year, its logic capacity improve at about 30% in a year; memory
speed at increase about 10% in a year and memory capacity at about 60% increase a year
also the disk capacity increase at a 60% a year and so overall cost per bit improves about
25% a year.
But before we go further with design and organization issues of parallel computer
architecture it is necessary to understand how computers had evolved. Initially, man used
simple mechanical devices – abacus (about 500 BC) , knotted string, and the slide rule for