Time Taken by this Algorithm in Terms of m, p, t_add, t_s and t_w

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SUMMARY

The discussion centers on the communication time of an algorithm as described in Question 4.8 from the provided link. The total time for communication is calculated using the formula T = (t_s + t_w * m) * log_2 p, where t_s is the start-up time, t_w is the per-word transfer time, m is the message size, and p is the number of processors. The user, Zulfi, questions whether the equation T = (t_s + t_w * m) * log_2 p + p * t_{add} is correct, where t_{add} represents additional time per processor. The community emphasizes the importance of reasoning over simply confirming answers.

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zak100
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Homework Statement
In short, the question says:
If each message contains m words and ##t_{add}## is the time to perform one addition, how much time does your algorithm take (in terms of m, p, ##t_{add}##, ##t_s## and ##t_w##)?
Relevant Equations
##T = (t_s + t_w*m) * log_2 p## i.e logp base 2
Hi,
Kindly consider the Question 4.8 on the following link
http://parallelcomp.uw.hu/ch04lev2sec18.html
##t_s## = start up time
##t_w## = per-word transfer time
m = size of message
p = number of processors
The total time for communication for ##logp## steps is:
##T = (t_s + t_w*m) * log_2 p## p=167 (see attached image p167... i.e equation (4.5)), equation to analyze(answer)
Is the time required equal to :

##T = (t_s + t_w*m) * log_2 p + p * t_{add}##

Note : image p168... contains description of algorithm (i.e Algorithm 4.9)

Some body please guide me is my equation (answer) correct or not?

Zulfi.
 

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