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

AI Thread Summary
The discussion focuses on analyzing the communication time for a specific algorithm, referencing equations related to startup time, per-word transfer time, message size, and the number of processors. The user questions whether their derived equation, which includes an additional term for processing time, is correct. The importance of reasoning in problem-solving is emphasized, encouraging a deeper understanding rather than simply confirming answers. Participants are invited to provide guidance based on the user's rationale. The conversation highlights the need for clarity in algorithm analysis and communication time calculations.
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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