Physics, 27.07.2019 00:20, notgoodatmath5379
Amultiprocessor machine has 1024 processors. on this machine we map a computation in which n iterate values must be computed and then exchanged between the processors. values are broadcast on a bus after each iteration. each iteration proceeds in two phases. in the ļ¬rst phase each processor computes a subset of the n iterates. each processor is assigned the computation of k = n/p iterates, where p is the number of processors involved. in the second, communication phase each processor broadcasts its results to all other processors, one by one. every processor waits for the end of the communication phase before starting a new computation phase. let t c be the time to compute one iterate and let t b be the time to broadcast one value on the bus. we deļ¬ne the computation-to-communication ratio r as t c /t b . note that, when p = 1, no communication is required. at ļ¬rst, we use the premise of amdahlās speedup (i. e., the same workload spread across an increasing number of processors). under these conditions: (a) compute the speedup as a function of p and r, for k = 1, 2, . . , 1024. (b) compute the maximum possible speedup as a function of p and r. (c) compute the minimum number of processors needed to reach a speedup greater than 1 as a function of p and r. second, we use the premise of gustafsonās law, namely that the uniprocessor workload grows with the number of processors so that the execution time on the multiprocessor is the same as that on the uniprocessor. assume that the uniprocessor workload computes 1024 iterates. (d) what should the size of the workload be (as a number of iterates) when p processors are used, as a function of p and r? pick the closest integer value for the number of iterates. (e) reconsider (a)ā(c) above in the context of growing workload sizes, according to gustafsonās law. third, we now consider the overhead needed to broadcast values over the bus. because of software and bus protocol overheads, each bus transfer requires a ļ¬xed amount of time, independent of the size of the transfer. thus the time needed to broadcast k iterate values on the bus by each processor at the end of each iteration is now t 0 + k Ć t b . (f) using the constant workload size assumption (as in amdahlās law), what is the maximum possible speedup? (g) using growing workload size assumption (as in gustafsonās law), what is the maximum possible speedup?
Answers: 1
Physics, 22.06.2019 06:50, saltytaetae
What is the stall speed at sea level of an airplane that weights 10000 lbs., has a wing area of 300ft^2, and a maximum lift coefficient of 1.4? what is the stall speed if flaps that double cl, max are applied?
Answers: 1
Physics, 22.06.2019 07:30, AnaiyaKirksey8
This is the substance(s) formed in a chemical reaction.
Answers: 1
Physics, 22.06.2019 10:10, natalieagustinlop54
Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.
Answers: 2
Physics, 22.06.2019 10:50, dontcareanyonemo
The temperature at a point (x, y) is t(x, y), measured in degrees celsius. a bug crawls so that its position after t seconds is given by x = 6 + t , y = 8 + 1 3 t, where x and y are measured in centimeters. the temperature function satisfies tx(3, 9) = 5 and ty(3, 9) = 4. how fast is the temperature rising on the bug's path after 3 seconds? (round your answer to two decimal places.)
Answers: 3
Amultiprocessor machine has 1024 processors. on this machine we map a computation in which n iterate...
Spanish, 31.10.2020 06:20
Mathematics, 31.10.2020 06:20
Law, 31.10.2020 06:20
Social Studies, 31.10.2020 06:20