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Parallel_Systems_4b M.E.Lock The context for this question i…

Parallel_Systems_4b M.E.Lock The context for this question is the same as the previous question. 4. Consider the following lock algorithm: while ((L == locked) or (T&S(L) == locked)) {    while (L == locked); // spin    delay (d[Pi]); // different delays for different processors  }  // success if we are here    b. [2 points] What are the program characteristics that would negatively impact the program’s performance with this lock algorithm implementation? In what way does it reduce performance? 

Parallel_Systems_5a M.E.Lock 5. Consider the ticket lock alg…

Parallel_Systems_5a M.E.Lock 5. Consider the ticket lock algorithm from lecture 4 (slide 108): a. [2 points] Compared with the lock algorithm with delay in a previous question, what is the advantage of ticket lock’s different method of determining the amount of delay? From a programmer’s perspective what is the added value of this algorithm compared to the lock algorithm with delay in the previous question? 

OS_Structure_1c Spin_and_Exokernel   The context for this qu…

OS_Structure_1c Spin_and_Exokernel   The context for this question is the same as the previous question. Exokernel uses a linear vector of time slots (or time quantum) to allot time for library OSes executing on top of Exokernel. Currently there are two library OSes running on top of the Exokernel.  OS1 is running a CPU-intensive long running ML training application  OS2 is running an interactive gaming application    c. [2 points] How does Exokernel maintain fairness for CPU time consumed by library OSes. 

Parallel_Systems_1 Shared Memory Machines 1. [2 points] Cons…

Parallel_Systems_1 Shared Memory Machines 1. [2 points] Consider a NCC-NUMA architecture for a shared address space multiprocessor.  What guarantees are needed from the architecture to ensure that it provides sequential consistency memory model to the programmer?