The trend of further miniaturization of electronic components, dramatic increase in power of microprocessor chips, and increase in capacity of main memory and hard disk continued during fifth generation. VLSI techonology became ULSI (Ultra-Large-Scale Integration) technology in fifth generation resulting in production of microprocessor chips having ten million electronic components. In fact, the speed of microprocessors and the size of main memory and dard disk doubled almost every eighteen months. As a result, many features found in the CPUs of large mainframe systems of third- and fourth generation systems became part of microprocessor architecture in fifth generation. This ultimately resulted in availability of very powerful and compact computers becoming available at cheaper rates and deadth of traditional large mainframe systems. Recently, processor manufacturers started building multicore processor chips instead of increasingly powerful (faster) single-core processor chips. The multicore chips improve overall performance by handling more work in parallel.
Due to this fast pace of advancement in computer technology, we see more compact and more powerful computers being introduced almost every year at more or less the same price or even cheaper. Notable among these are portable notebook computers that give the power of a PC to their users even while travelling, powerful desktop PCs and workstation, powerful servers, powerful supercomputers, and handled computers. (see Chapter 20 for detailed description of these types of computers).
Storage technology also advance making larger main memory and disk storage available in newly introduced systems. Currently, PC having few Gigabytes (GB) of main memory and 80 to 320 Gigabytes (GB) of hard disk Gigabytes of hard disk capacity are common. RAID (Redundant Array of Inexpensive Disks) technology enables configuration of a bunch of disks as a single large disk. It, thus supports large hard- disk space with better in-built reliability. During fifth generation, optical disk (popularly known as Compact Disks or CDs) emerged as a popular portable mass storage media.
In the area of large-scale systems, fifth generation saw the emergence of more powerful supercomputers based on parallel processing technology. They used multiple processors and were of two types- shared memory and distributed memory parallel computers. In a shared memory parallel computer, a high-speed bus or communication network interconnects a number of processors to a common main memory, where as in a distributed memory parallel computer, a communication network interconnects a number of processors, each with its own memory. These systems use parallel programming technique to break a problem into smaller problems and execute them in parallel on multiple processors of the system. Processors of a shared memory parallel computer use message-passing mechanism for communication. Distributed memory parallel computers have better scalability (can grow larger in capability)than shared memory parallel computers, and are now built by clustering together powerful commodity workstations by using a high-speed commodity switched network. This is known as clustering technology.
During fifth-generation, the Internet emerged with associated technologies and applications. It made it possible for computer users sitting across the globe to communicate with each other within minutes by use of electronic mail (known as e-mail) facility. A vast ocean of information became readily available to computer users through the World Wide Web (known as WWW). Moreover, several new types of exciting applications like electronic commerce, virtual libraries, virtual classrooms, distance education, etc emerged during the period.
The tremendous processing power and the massive storage capacity of fifth-generation computers also made them a very useful and popular tool for a wide range of multimedia applications dealing with information containing text, graphics, animation, audio, and video data. In general, data size for multimedia information is much larger than plan text information because representation of graphics, animation, audio, or video media in digital form requires much larger number of bits than that required for representation of plan text. Because of this, multimedia computer systems require faster processor, large storage devices, larger main memory, good graphics terminal, and input/output devices required to play any audio associated with a multimedia application program. The availability of multimedia computer systems resulted in a tremendous growth of multimedia applications during fifth-generation.
In the area of operating systems, some new concepts that gained popularity during fifth-generation include microkernels, multithreading, and multicore operating systems. Microkernel technology enablesled designers to model and design operating systems in a modular fashion. This makes operating systems easier to design and implement, easier to modify or add new services, and allows users to implement and use their own service. Multithreading technology is a popular way to improve application performance through parallelism. In traditional operating systems, basic unit of CPU scheduling is a thread. In such operating systems, a process consists of an address space containing its instructions and data, and one or more threads sharing same address space. Hence, these systems can create a new thread, switch CPU between threads, and share resources between threads of same process more efficiently than between processes, resulting in faster execution and better overall system performance. A multicore operating system can run multiple programs at the same time on multicore chip with each core handling a separate program.
In the area of programming languages, concepts that gained popularity during fifth generation are JAVA programming language, and parallel programming libraries like MPI (Message Passing Interface) and PVM (Parallel Virtual Machine). JAVA is used primarily on the World Wide Web. It supports Java-based applets allowing web pages to have dynamic information and more interactivity with users of web information. MPI and PVM libraries enable development of standardized parallel programs, so that a programmer can easily port and execute a parallel program developed for one parallel computer on other parallel computers. MPI is used for distributed memory parallel computers and PVM is used for shared memory parallel computers.
Characteristic features of fifth-generation computers are as follows:-
Portal PCs (called notebook computers) are much smaller and handly than PCs fourth-generation allowing users to use computing facility even while travelling.
fifth-generation desktop PCs and workstation are several times more powerful than PCs of fourth generation.
Although fifth-generation mainframe and supercomputers require proper air-condditioning of the rooms/areas in which they are located, no air-conditioning is normally required for notebook computers, desktop PCs, and workstation.
They consume less power than their predecessors do.
They are more reliable and less prone to hardware failures than their predecessors were, requiring negligible maintenance cost.
Many of the large-scale fifth-generation systems have hot-plug feature that enables a failed component to be replaced with a new one without the need to shutdown the system. Hence, the uptime of these systems is very high.
They have faster and larger primary and secondary storage as compared to their predecessors.
They are general-purpose machines.
Their manufacturing does not require manual assembly of individual components into electronic circuits resulting in reduced human labor and cost involved at assembly stage. Hence, commercial production of these systems is easier and cheaper. However, highly sophisticated technology and expensive setup (affordable only by a few organizations in the world) is required for manufacturing ULSI chips.
Use of standard high-level programming languages allows programs written for one computer to be easily ported to and executed on another computer.
More user-friendly interfaces with multimedia features make the systems easier to learn and use by anyone, including children.
Newer and morefully applications, including multimedia applications, make the systems more useful in every occupation.
Explosion in the size of the Internet coupled with Internet-based tools and applications have made these systems influence the life of even common people.
These systems also use the concept of unbundled software and add-on hardware allowing the users to invest only in the hardware configuration and software of their need and value.
With so many types of computers in all price ranges today, we have a computer for almost any type of user whether the user is a child or a world-fame scientist.