What data structure is used by an operating system to keep track of process information? Explain
A data structure termed as process control block (PCB) is used by an operating system to keeps track of all information relating a process. The PCB of a process consists of the subsequent information.
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Process ID
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Priority
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Process state
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PSR
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Registers
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Event information
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Memory allocation
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Resources held
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PCB pointer
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(a) Process scheduling information: This information contains three fields process ID, process state, priority.
(b) PSR and machine registers: These fields have contents of the processor states register (PSR) and the machine registers while the execution of the process was final suspended.
(c) Event information: While a process is in blocked state, this field consists of information concerning the event for that the process is waiting.
(d) Memory and resource information: Such information is helpful for the de-allocating memory and resources while the process terminates.
(e) PCB pointer: This is a pointer to the next PCB in the process scheduling list.