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(a) What is the cycle time that maximizes performance without allocating multiple cycles to a segment?
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(b) What is the total time to execute the function (through all stages)?
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(c) What is the cycle time that maximizes performance if each segment can be partitioned into sub-segments?
2. Repeat problem 1 if there is a 1 ns clock skew (uncertainty of ±1 ns) in the arrival of each clock pulse.
3. A four-segment pipeline to execute a function has the following parameters:
Segment #PmaxPmin
1147ns
2129ns
31610ns
4115ns

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The clock overhead, C, for each register stage is 3ns.
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(a) If no controlled clock skew is allowed, what is the latency of execution (through all stages) for the function? What is the minimum cycle time?
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(b) If we now allow controlled clock skew to take advantage of Pmin what is the latency, minimum cycle time, and clock skew required at each stage?
4. Repeat problem 3 if there is an additional 1 ns of uncertainty in the arrival of the clock at each segment.
5. Plot Soptwith respect to clock skew factor (k) for k = 0.05 to k = 0.20. Assume T = 120ns, C = 5ns, and b = 0.2.
6. We can generalize the equation for Sopt/sub> by allowing for pipeline interruption delay of S -a cycles (rather than S - 1), where S >a ³ 1. Find the new expression for Sopt.
7. (a) Show that the effect of uncontrolled clock skew(±d) in a regular pipeline is to increase C, and hence cycle time, by 2d.
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(b) Show that the effect of uncontrolled clock skew (±d) in a wave pipeline is to increase C, and hence cycle time, by 4d.
8. Repeat Study 2.1, with the delay in R®ALU®R = 16 ns and instruction and data cache data access = 8ns.
9. Acertain pipeline has the following functions and functional unit delays (without clocking overhead):
FunctionDelay
A
6
B
8
C
3
D
7
E
9
F
5

 
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