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Memory Management

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Memory Management Most computers nowadays are capable of holding several programs in memory simultaneously, so that a user can switch from one application to another. The operating system has to allocate memory to each application - as well as to itself! If the OS detects that there is insufficient memory to load an application that the user has asked for, it may swap another application (or part of it) ...read more.


The technique of swapping part of the contents of memory out to disk is known as virtual memory, because it makes the computer appear to have more memory than it actually does. Resource Allocation and Scheduling In larger computer systems which are capable of running several programs at once (multiprogramming), the OS is responsible for allocating processing time, memory and input-output resources to each one. ...read more.


keyboard, a printer sending a message that it is out of paper, the realtime clock interrupting to indicate that the processor should be allocated to the next user in a multiuser system, a hardware or software malfunction. User-Computer Communication The user gives instructions to the computer to start a program, copy a file, send a message to another user, and so on by typing in commands recongnised by the operating system ...read more.

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