3.1.2 Process Table

The operating system manages processes by the way of having the process table. For the system, each process is represented as an entry in the process table. Each entry of the given process is often known as process control block (PCB) or process table field. Each entry contains certain pieces of information about a process, and normally includes the following:

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Process state: How a process is being executed.

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Registers: Program counters (PC) and other sets of registers depending on the CPU architecture.

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Scheduling information: Priority, order of queue, and other scheduling parameters.

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Memory Management: Amount of allocated memory, etc.

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Identification: Process ID, user and group ID's of who owns the process, and permissions.

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Input / Output information: List of opened communications to the I/O, such as file descriptors and sockets.

Note that the set of entry may vary by operating systems depending on necessary information [SPG91]