Spring OS The context for this question is the same as the previous question. You are a software engineer on a team that maintains an important application that runs on Spring OS. Currently, Client Domain A, Client Domain B, Server Domain Y and Server Domain Z all run on a single node. Assume Server Z exports Object Z and Server Y exports Object Y. Recently, the entire application has been running slow. To improve system performance and scalability, your manager has proposed partitioning the domains across two nodes connected by a LAN. Proposed Split: Node 1: Client Domain A, Server Domain Z Node 2: Client Domain B, Server Domain Y b) [3 Points] Object Y supports both read and write operations. Client A must have read/write access to Y, while Client B must have read only access to Y. Using succinct bullets, state how the Spring mechanisms (capabilities, access control, doors) allow achieving the desired objectives.

RPC Latency Limits The context for this question is the same as the previous question. Some client process C is making an RPC call to server process S. The amount of time for this RPC call to execute, t, can be represented as an expression of the following variables: tc – the time to copy n bytestx – the time to context switch between process P and P’tn – the time to transmit n bytes over the networkts – the time for procedure P to execute on S b) [2 points] Additionally, the kernel guarantees that any context switches occur after any data is transmitted. Provide an updated expression for t. Explain your reasoning.

Distributed Shared Memory The context for this question is the same as the previous question. Consider the following sequence of actions in a TreadMarks DSM system. Assume pristine copies of pages X and Y are at their owner node O throughout. Assume X and Y are initially not present on any other node. T1: Processor P1:acq(L1)write Xrel(L1)T2: Processor P2:acq(L1)write Yrel(L1)T3: Processor P3:acq(L2)write Xrel(L2)T4: Processor P4:acq(L1)read Xwrite Yrel(L1) c) [2 points] What happens when P4 releases L1?

Lamport’s Logical Clock The context for this question is the same as the previous question. In the questions below, DB-A, DB-B, and DB-C represent a replicated database. For all questions in this section, explain your reasoning in one or two sentences. Correct justification is required to receive full credit. c) [3 points] Assume the replicated database stores a single key x. Write W1 updates x = 1 Write W2 updates x = 2 A read is called globally consistent if, at the time it is served, all replicas would return the same value of x. Now suppose we add a new event Rc, on DB-C, where Rc is a client read of x, and it occurs after c3 but before c4. Will the read at Rc be globally consistent? State yes or no and explain your reasoning in one or two sentences.

Global Memory Systems The context for this question is the same as the previous question. Based on the Global Memory Systems (GMS) architecture, analyze the following multi-node scenario. Use the provided terminology for your answers. For any given page: PFD States: Local-Private — node owns an exclusive local copy, Local-Shared — multiple nodes hold shared copy, Global-Private – node holds the page in its global memory on behalf of another node, Non-existent — node does not hold any copy. GCD:  Home Node for a given page; given a UID it returns the node IDs that are currently hosting the page in set notation, e.g., {X, Y} Initial Scenario (Time T0) A 3-node cluster consists of Node A, Node B, and Node C. For the data page P, Node A is the Home Node. At T0, Node A has just loaded Page from disk into its local part of the DRAM for a process. Nodes B and C are currently idle. Current Status at T0 with respect to page P: GCD at Home Node for P: {A} PFD at Node A: Local-Private PFD at Node B: non-existent PFD at Node C: non-existent c) [2 points] Event 2 (Time T2>T1) Node A experiences memory pressure and intends to evict Page P. The page is clean (i.e., not dirty). Node C would be the candidate node to send the page. Should Node A decide to keep the page in the cluster. Provide the status for the following 4 entries after Event 2: [0.5 points] GCD Owner List at Home Node: (List) ________ [0.5 points] PFD at Node A: (State) __________ [0.5 points] PFD at Node B: (State) __________ [0.5 points] PFD at Node C: (State) __________

Active Networks The context for this question is the same as the previous question. Consider three active nodes A → B → C in sequence. Capsule originates at A and passes through B before reaching C. Node B currently has the code for this TYPE in its soft store, but node C has not seen this TYPE before. A new capsule of this TYPE now arrives at C. b) [2 points] Now suppose that, unlike in (a), B’s soft store was recently cleared due to a router restart and no longer has the code for this TYPE. How does this change the outcome at C? What does this tell us about the robustness of the PREV-based design?

Global Memory Systems Based on the Global Memory Systems (GMS) architecture, analyze the following multi-node scenario. Use the provided terminology for your answers. For any given page: PFD States: Local-Private — node owns an exclusive local copy, Local-Shared — multiple nodes hold shared copy, Global-Private – node holds the page in its global memory on behalf of another node, Non-existent — node does not hold any copy. GCD:  Home Node for a given page; given a UID it returns the node IDs that are currently hosting the page in set notation, e.g., {X, Y} Initial Scenario (Time T0) A 3-node cluster consists of Node A, Node B, and Node C. For the data page P, Node A is the Home Node. At T0, Node A has just loaded Page from disk into its local part of the DRAM for a process. Nodes B and C are currently idle. Current Status at T0 with respect to page P: GCD at Home Node for P: {A} PFD at Node A: Local-Private PFD at Node B: non-existent PFD at Node C: non-existent a) [2 points] Event 1 (Time T1>T0) A process on Node B page faults on Page P. Provide the status for the following 4 entries after Event 1: [0.5 points] GCD at Home Node for P: (List) __________ [0.5 points] PFD at Node A: (State) __________ [0.5 points] PFD at Node B: (State) __________ [0.5 points] PFD at Node C: (State) __________

Active Networks [3 points] A student proposes embedding full code directly in every capsule instead of using a TYPE field and soft store. Give one advantage and one disadvantage of this proposal.

Global Memory Systems The context for this question is the same as the previous question. Based on the Global Memory Systems (GMS) architecture, analyze the following multi-node scenario. Use the provided terminology for your answers. For any given page: PFD States: Local-Private — node owns an exclusive local copy, Local-Shared — multiple nodes hold shared copy, Global-Private – node holds the page in its global memory on behalf of another node, Non-existent — node does not hold any copy. GCD:  Home Node for a given page; given a UID it returns the node IDs that are currently hosting the page in set notation, e.g., {X, Y} Initial Scenario (Time T0) A 3-node cluster consists of Node A, Node B, and Node C. For the data page P, Node A is the Home Node. At T0, Node A has just loaded Page from disk into its local part of the DRAM for a process. Nodes B and C are currently idle. Current Status at T0 with respect to page P: GCD at Home Node for P: {A} PFD at Node A: Local-Private PFD at Node B: non-existent PFD at Node C: non-existent b) [1 point] Event 2 (Time T2>T1) Node A experiences memory pressure and intends to evict Page P. The page is clean (i.e., not dirty). Node C would be the candidate node to send the page. Should Node A decide to keep the page in the cluster. (Answer True/False with justification. No credit without justification): Node A will send the Page P to Node C’s global part of the DRAM.

41. After winning the lottery, a couple bought a new estate home and started a collection of fine art and luxury vehicles. They soon found that they had ascended into a new bracket of wealth. The term to refer to the movement of one’s class position, upward or downward, in stratified societies is