An example would be two CPUs dedicated to one system which divides the work

An example would be two cpus dedicated to one system

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computing environment. An example would be two CPUs dedicated to one systemwhich divides the work between them. Another would be using one CPU as atelecommunications control unit hooked to a host computer that is used forapplication processing.SYSTEMSTHEORYANDMANAGEMENTINFORMATIONSYSTEMS
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280Lesson NineQUESTION FIVE(a)Multiprogramming means having several jobs (programs and data) in computer’smain memory at the same time. The memory is partitioned into several pieces with adifferent job in each partition. This type of program execution is known asconcurrent/alternate execution. The programs do not execute simultaneously butexecute in overlapped fashion, with the CPU concentrating on only one at a time.While one job is waiting for input/output, the CPU switches to and executes anotherjob. When that job needs to wait the CPU switches to another job and so on.Eventually a waiting job finishes waiting and gets back the CPU. Advantages ofmultiprogramming includes:Elimination of CPU idle time (the processor is kept busy all the time)Improves computer efficiency since many jobs are processed at a muchlesser time and resources are utilized maximally.(b)Data are raw facts about the organization and its business transactions. Most dataitems have little meaning and use by themselves.Information is data that has been refined and organized by processing and purposefulintelligence. The latter, purposefulintelligenceis crucial to the definition – peopleprovide the purpose and the intelligence that produces true information.(c)The combined size of the program, data and stack may exceed the amount ofphysical memory available for it. Virtual memory refers to the ability to address astorage space much larger than that available in primary storage. The system splitsup programs into pieces and swaps them into and out of memory as required fromdisk storage. The program generated addresses are called virtual addresses andconstitute the virtual address space. Even though running program generates virtualaddresses, the program resides/executes in real memory. Hence the virtual addressesmust be mapped onto real memory during execution.Virtual memory may be implemented using paging or segmentation. Both providesmechanisms for:Translating virtual addresses to real addresses during executionAllowing a program to reside partly in memory and partly on secondary storage.The operating system keeps those parts of the program currently in use in mainmemory, and the rest on disk. The program occupies non-contiguous (small blocksof memory that are scattered all over the storage space) memory locations.(d) Compilers/interpreters – these are for the purposes of translating a program fromits object code to its source code so that it can be executed.Debuggers – useful for detecting bugs, their location within a program, pointingout what is wrong and may suggest possible solutions for correcting the bug(error)
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  • Spring '15
  • wauye
  • The Land, ........., STRATHMORE UNIVERSITY

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