Thread Control Block in Operating System

Very similar to Process Control Blocks (PCBs) which represents processes, Thread Control Blocks (TCBs) represents threads generated in the system. It contains information about the threads, such as it’s ID and states.

The components have been defined below:

  • Thread ID: It is a unique identifier assigned by the Operating System to the thread when it is being created.
  • Thread states: These are the states of the thread which changes as the thread progresses through the system
  • CPU information: It includes everything that the OS needs to know about, such as how far the thread has progressed and what data is being used.
  • Thread Priority: It indicates the weight (or priority) of the thread over other threads which helps the thread scheduler to determine which thread should be selected next from the READY queue.
  • A pointer which points to the process which triggered the creation of this thread.
  • A pointer which points to the thread(s) created by this thread.

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