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Virtualization_1a Full Virtualization   1. The above figure illustrates a memory translation scheme in a fully virtualized environment. In this setup, the Virtual Page Number (VPN) is first translated to a Physical Page Number (PPN), which is then mapped to a Machine Page Number (MPN). The guest OS page tables store the VPN-PPN mappings, while the shadow page table maintains the PPN-MPN mappings.    a. [2 points] How does the MPN differ from the PPN, and why is it needed?

Virtualization_1b Full Virtualization   The context for this question is the same as the previous question: 1. The above figure illustrates a memory translation scheme in a fully virtualized environment. In this setup, the Virtual Page Number (VPN) is first translated to a Physical Page Number (PPN), which is then mapped to a Machine Page Number (MPN). The guest OS page tables store the VPN-PPN mappings, while the shadow page table maintains the PPN-MPN mappings.    b. [1 points] Can you point out a glaring inefficiency in this scheme compared to a non-virtualized setting?

OS_Structure_4c Microkernel The context for this question is same as the previous question. 4. You are building an OS using a microkernel-based approach following the principles of the L3 microkernel. The processor architecture you are building this OS for has the following features:      • A 32-bit hardware address space.    • Paged virtual memory system (8KB pages) with a processor register called PTBR that points to the page table in memory to enable hardware address translation.     • A TLB with Address space IDs associated with each TLB entry.     • A pair of hardware-enforced segment registers (lower and upper bound of virtual addresses) which limit the virtual address space that can be accessed by a process running on the processor.     • A virtually-indexed physically tagged processor cache. You end up with 2 big subsystems (A and B) that each require 230 bytes of virtual memory space. You also end up with 4 subsystems (C,D,E,F) that require 100×220 , 500×220 , 1000×220 , and 2000×220 bytes of virtual memory, respectively. You want to put each of these subsystems in their own protection domains.  c. [2 points] (Answer this question based on your grouping of the protection domains) There is a context switch from A to B. What does your OS do to facilitate this context switch? 

Virtualization_2b Full Virtualization   The context for this question is the same as the previous question: 2. CPU virtualization mechanisms in a virtualized environment have two primary objectives. Providing each guest OS with the illusion of exclusive CPU ownership.  Delivering program discontinuity events to the guest OS.   b. [1 point] How are these events delivered to the guest OS in a fully virtualized setting?

Parallel_Systems_4 Barriers 4. [3 points] Consider the sense reversing barrier implementation in C as follows where count, sense are shared variables which are initialized to N and False respectively. Will this code work? If yes explain why, if no, give brief reasoning and an example! 

Virtualization_3 Memory Management   3. [2 Points] In VM oblivious page sharing, what are the main performance overheads compared to using dedicated machine memory pages for each VM?

When people try to harm others via social media, it is referred to as:

Juan is a religious conservative and identifies as gender nonbinary. They feel troubled at times because their two identities conflict with each other. This is referred to as:

Family structure refers to:

Kayla called her friend Sue on Saturday to see whether Sue wanted to go to the movies. Sue told Kayla she was staying home to study for their upcoming history test. After the call, Kayla decided to study instead of go to the movies. Kayla was experiencing: