The following diagram shows three process states In theory w

The following diagram shows three process states. In theory, we could have six transitions with three states, i.e., two transitions between each pair of states. The diagram, however, only includes four transitions. Could either or both of the missing transitions occur? If so, under which circumstances?

Solution

Consider the diagram:
• The diagram represents ‘Running’, ‘Blocked’, and ‘Ready’ states for process running.
• The conceivable transition is from ‘Blocked’ state to ‘Running’ state.
• If the CPU is an idle state then the process running directly from the ‘Blocked’ state to ‘Running’ state. Otherwise, process transition from the ‘Ready’ state to ‘Blocked’ state is impossible.
• While a ‘Ready’ process could not perform the I/O operations or anything else that cannot block it. So, only the running process can easily be blocked.