Process, memory, and Storage Management in OS, Summaries of Operating Systems

Download Process, memory, and Storage Management in OS and more Summaries Operating Systems in PDF only on Docsity! PROCESS, MEMORY & STORAGE MANAGEMENT U U U U PROCESS MANAGEMENT A process is a program in execution. It is a unit of work within the system. Program is a , process is an . Process needs resources to accomplish its task . CPU, memory, I/O, files . Initialization data Process termination requires reclaim of any reusable resources MEMORY MANAGEMENT U To execute a program all (or part) of the instructions must be in memory U All (or part) of the data that is needed by the program must be in memory. U Memory management determines what is in memory and when . Optimizing CPU utilization and computer response to users U Memory management activities . Keeping track of which parts of memory are currently being used and by whom . Deciding which processes (or parts thereof) and data to move into and out of memory . Allocating and deallocating memory space as needed MASS-STORAGE MANAGEMENT Usually disks used to store data that does not fit in main memory or data that must be kept for a “ long” period of time Proper management is of central importance OS activities . Free- space management . Storage allocation . Disk scheduling U U U U Entire speed of computer operation hinges on disk subsystem and its algorithms U Some storage need not be fast . Tertiary storage includes optical storage, magnetic tape . Still must be managed – by OS or applications . Varies between WORM (write-once, read- many-times) and RW (read-write) CACHING d Cache is a type of memory that is used to increase the speed of data access. d The process of storing and accessing data from a cache is known as caching. d Cache Management