Operating Systems Midterm Exam Questions with Correct Answers Latest Update 2025/2026
What is the main advantage of the microkernel approach to system design? How do user
programs and system services interact in a microkernel architecture? What are the
disadvantages? - Answers Advantages:
-Extending the OS is made easier
-Fewer changes need to be made when modifying the kernel
-OS is easier to port from one hardware design to another
Disadvantages:
-system function overheads which affect the performance of microkernel
-interprocess communication comes with overheads
In what ways is the modular kernel approach similar to the layered approach? In what ways
does it differ from the layered approach? - Answers The modular kernel approach requires
subsystems to interact with each other through carefully constructed interfaces. The layered
kernel approach imposes a strict ordering of subsystems such that subsystems at lower layers
are not allowed to invoke operations corresponding to upper layer subsystems. These
restrictions don't exist in the modular kernel approach.
What are two models of inter-process communication? What are the strengths and weaknesses
of the two approaches? - Answers The message-passing model and the shared memory model.
Message passing is slower than shared memory but it is useful for exchanging small amounts
of data, and is easier to implement. Shared memory model allows two of more processes to
exchange info by reading and writing data in shared memory areas. It offers better convenience
of communication. It has security and synchronization issues.
What is the main advantages for an operating system designer of using a virtual machine
architecture? - Answers System is easy to debug, and security problems are easy to solve. VMs
provide a good platform for OS research since many OS systems can run on one physical
machine.
What is the relationship between a guest operating system and a host operating system in a
system like VMware? What factors need to be considered in choosing the host operating
system? - Answers A guest operating system provides its services by mappingthem onto the
functionality provided by the host operating system. A key issue that needs to be considered in
choosing the host operating system is whether it is sufficiently general in terms of its system-
call interface in order to be able to support the functionality associated with the guest operating
system.
If a program terminates abnormally, a dump of memory may be examined by a _______ to
What is the main advantage of the microkernel approach to system design? How do user
programs and system services interact in a microkernel architecture? What are the
disadvantages? - Answers Advantages:
-Extending the OS is made easier
-Fewer changes need to be made when modifying the kernel
-OS is easier to port from one hardware design to another
Disadvantages:
-system function overheads which affect the performance of microkernel
-interprocess communication comes with overheads
In what ways is the modular kernel approach similar to the layered approach? In what ways
does it differ from the layered approach? - Answers The modular kernel approach requires
subsystems to interact with each other through carefully constructed interfaces. The layered
kernel approach imposes a strict ordering of subsystems such that subsystems at lower layers
are not allowed to invoke operations corresponding to upper layer subsystems. These
restrictions don't exist in the modular kernel approach.
What are two models of inter-process communication? What are the strengths and weaknesses
of the two approaches? - Answers The message-passing model and the shared memory model.
Message passing is slower than shared memory but it is useful for exchanging small amounts
of data, and is easier to implement. Shared memory model allows two of more processes to
exchange info by reading and writing data in shared memory areas. It offers better convenience
of communication. It has security and synchronization issues.
What is the main advantages for an operating system designer of using a virtual machine
architecture? - Answers System is easy to debug, and security problems are easy to solve. VMs
provide a good platform for OS research since many OS systems can run on one physical
machine.
What is the relationship between a guest operating system and a host operating system in a
system like VMware? What factors need to be considered in choosing the host operating
system? - Answers A guest operating system provides its services by mappingthem onto the
functionality provided by the host operating system. A key issue that needs to be considered in
choosing the host operating system is whether it is sufficiently general in terms of its system-
call interface in order to be able to support the functionality associated with the guest operating
system.
If a program terminates abnormally, a dump of memory may be examined by a _______ to
