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Fill in SPIN or BLOCK in the following sentences: A. On a uniprocessor system, if thread T1 tries to lock a mutex that has already been locked by T2, by default T1 will . B. On a multiprocessor system, if thread T1 tries to lock a mutex that has already been locked by T2, by default T1 will .C. Given the adaptive mutex proposed in the Solaris papers, if thread T1 tries to lock a mutex that has already been locked by T2, T1 will if T2 is currently executing.D. Given the adaptive mutex proposed in the Solaris papers, if thread T1 tries to lock a mutex that has already been locked by T2, T1 will if T2 is not currently scheduled.

Do the following statements refer to an OS mechanism (M), abstraction (A) or policy (P)? Enter M, A, or P in each text box.    a) The OS represents communication endpoints as sockets.  b) A process can wait for incoming connections on sockets via accept().  c) A socket number may be reused.  d) A process can open up to SOME_MAX_NUMBER sockets.  e) All threads in an address space can access all sockets opened by anyone in the process.  

In a file server, the following steps have to be performed on each request: (1) parse request, (2) find and read file, (3) respond with file or error message. Assume steps (1) and (3) take 1ms and step (2) takes 2ms. Assume any delays due to inter-thread communication, synchronization, context-switching, etc. are negligible. Assume you have infinite resources. Consider a boss-worker and a pipelined model designs, each with a total of 4 threads. In both cases, you need to process a total of 6 requests. Answer the questions below. Please try to follow these rules:- Do not write the units. – Do not use a comma in your answer (e.g., write 1000 instead of 1,000 or write 0.75 instead of 0,75). – Write the leading zero in decimal fractions (e.g., write 0.75 instead of .75)- Show the results with up to two decimal places. Questions:For the boss-worker model, where the boss simply accepts requests and passes them onto a shared workers’ queue: a) How many requests can be processed concurrently? b) How long does it take to process a total of 6 requests in ms? ms c) What is the average throughput for this workload, in req/ms? req/ms d) What is the average response time for this workload, in ms? ms For a balanced implementation of the pipeline model: e) How many threads are allocated to the first stage? f) How many threads are allocated to the second stage? g) How many requests are concurrently being processed? h) How long does it take to process a total of 6 requests in ms? ms i) What is the average throughput for this workload, req/ms? req/ms j) What is the average response time for this workload, in ms? ms 

The most artfully designed dessert presentations combine varied tastes and textures in a symmetrical arrangement.

Abigail Adams divorced her husband, John, and married Benjamin Franklin.  

Marrons glacés are

Tempering ____________________fat molecules in chocolate so that the chocolate stays shiny and crisp after molds.

Chocolate should be evaluated based on its appearance, smell, break and texture.

Pastillage is prized for its smooth texture, ability to be easily molded and its delicate taste.

When coating petits fours, the fondant should be thick enough to cover the top and sides of the cake with an opaque layer of icing.