Process table

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In computer science , the process table is a tabular data structure that contains one entry for each running process . This is called the process control block ( process context ; English p rocess c ontrol b lock or t ask c ontrol b lock , short PCB or TCB ). The process control block contains information about the status of the process, its command counter , CPU register, its stack pointer as well as its memory allocation and the status of its open files. Further contents in the data record are scheduling and management information as well as all information that has to be saved when the process changes from the "active" state to the "ready" or "blocked" states in order to guarantee a seamless continuation after the interruption .

These breaks are necessary for two reasons: On the one hand, the user wants a high degree of parallelism. On the other hand, the number of running programs (processes) is much larger than the number of available processors (even with multi-core processors). The process table is therefore a data structure maintained by the operating system in order to be able to carry out runtime interruptions in processes.

In Linux, process control blocks are represented by the C- struct task_struct.

See also

Individual evidence

  1. ^ Abraham Silberschatz, Peter B. Galvin, Greg Gagne: Operating system concepts . 7th edition. John Wiley & Sons, Hoboken 2005, ISBN 0-471-69466-5 , pp. 83 (English).
  2. ^ Abraham Silberschatz, Peter B. Galvin, Greg Gagne: Operating system concepts . 7th edition. John Wiley & Sons, Hoboken 2005, ISBN 0-471-69466-5 , pp. 86 (English).