What happens when a child process becomes an Orphan Process in Unix?
When a parent process terminates before its child process, the child becomes an orphan and is automatically adopted by the init process (PID 1), which periodically reaps zombie status.
Which component of the OS is responsible for selecting a process from the ready queue and allocating the CPU to it?
The Short-term (CPU) scheduler selects among the processes in memory that are ready to execute and allocates CPU time to them. Long-term handles job submission, and Medium-term handles swapping.
What is the primary role of the Medium-Term Scheduler?
The Medium-term scheduler reduces the degree of multiprogramming by swapping out processes from main memory to disk and swapping them back when memory frees up.
Context switching time in an operating system is considered as:
Context switching involves saving the state of the currently running process and loading the saved state for the new process. During this time, no productive user computation occurs, so it is pure system overhead.
Which thread model maps multiple user-level threads to a single kernel-level thread?
In the Many-to-One model, many user-level threads are mapped to a single kernel thread. If one thread makes a blocking system call, the entire process blocks because the kernel sees only one thread.