Question: Table 3.13 shows the process states
Table 3.13 shows the process states for the VAX/VMS operating system.
Table 3.13:
a. Can you provide a justification for the existence of so many distinct wait states?
b. Why do the following states not have resident and swapped-out versions: Page Fault Wait, Collided Page Wait, Common Event Wait, Free Page Wait, and Resource Wait?
c. Draw the state transition diagram and indicate the action or occurrence that causes each transition.
Transcribed Image Text:
Table 3.13 VAX/VMS Process States Process Process Condition State Currently Running process. Executing Computable Ready and resident in main memory. (resident) Computable Ready, but swapped out of main memory. (outswapped) Page Fault Process has referenced a page not in main memory and must wait Wait for the page to be read in. Collided Process has referenced a shared page that is the cause of an Page Wait existing page fault wait in another process, or a private page that is in the process of being read in or written out. Common Waiting for shared event flag (event flags are single-bit interprocess Event Wait signaling mechanisms). Free Page Waiting for a free page in main memory to be added to the Wait collection of pages in main memory devoted to this process (the working set of the process). Hibernate Process puts itself in a wait state. Wait (resident) Hibernate Hibernating process is swapped out of main memory. Wait (outswapped) Local Event Process in main memory and waiting for local event flag (usually VO Wait completion). (resident) Local Event Process in local event wait is swapped out of main memory. Wait (outswapped) Suspended Process is put into a wait state by another process. Wait (resident) Suspended Suspended process is swapped out of main memory. Wait (outswapped) Resource Process waiting for miscellaneous system resource. Wait
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