(PCB) or Task Control Block (TCB)





(PCB) or Task Control Block (TCB)

• As the operating system supports multi-programming, it needs to keep track of all the processes



•  The process control block (PCB) is used to track the process’s execution status.



• Each block of memory contains information about the process state, program counter, stack pointer, status of opened files, scheduling algorithms, etc.



• All these information is required and must be saved when the process is switched from one state to another.



• The process table is an array of PCB’s, that means logically contains a PCB for all of the current processes in the system.

(PCB)



• Process table is an array or linked list


• The process table is an array of PCB’s, that means logically contains a PCB for all of the current processes in the system.


Pointer – It is a stack pointer which is required to be saved when the process is switched from one state to another to retain the current position of the process.

Process state – It stores the respective state of the process.

Process number -
Every process is assigned with a unique id known as process ID or PID which stores the process identifier.

Program counter – It stores the counter which contains the address of the next instruction that is to be executed for the process.
Register – These are the CPU registers which includes: accumulator, base, registers and general purpose registers.

Memory limits – This field contains the information about memory management system used by operating system. This may include the page tables, segment tables etc.


Open files list – This information includes the list of files opened for a process.


Miscellaneous accounting and status data – This field includes information about the amount of CPU used, time constraints, jobs or process number, etc.

Comments

  1. sathishSeptember 10, 2019 at 12:56 AM

    This comment has been removed by the author.

    ReplyDelete
  2. Gowri ShankarSeptember 10, 2019 at 12:57 AM

    Nice sir......

    ReplyDelete
  3. Gnana Surya PSeptember 10, 2019 at 1:03 AM

    Very nice and useful to me sir...

    ReplyDelete
  4. indhuSeptember 10, 2019 at 1:04 AM

    very nice sir...

    ReplyDelete
  5. PriyaSeptember 10, 2019 at 1:08 AM

    nice sir...

    ReplyDelete
  6. NivedhaSeptember 10, 2019 at 1:09 AM

    Nice sir and easy ato understand sir

    ReplyDelete
  7. AnonymousSeptember 10, 2019 at 1:20 AM

    useful to me ....

    ReplyDelete
  8. indhuSeptember 11, 2019 at 9:04 AM

    In this blog I understand the concept of pcb and tcp and miscellaneous accounting and status data is a new one ... concept to me ...thank you sir...

    ReplyDelete
  9. Gnana Surya PSeptember 11, 2019 at 11:33 AM

    The concepts of PCB and TCP along with the process table, stack pointer and register are very nice Sir...

    ReplyDelete
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