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

In summary, the conversation is about a question regarding the total time for communication for a certain number of steps and processors. The question involves the variables ##t_s##, ##t_w##, m, and p, and the equation to analyze is ##T = (t_s + t_w*m) * log_2 p## p=167. The person is asking for guidance on whether their equation is correct or not and is directed to provide their reasoning for the answer.
  • #1
zak100
462
11
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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Related to Time Taken by this Algorithm in Terms of m, p, t_add, t_s and t_w

1. How does the value of m affect the time taken by this algorithm?

The value of m, which represents the size of the input data, has a direct impact on the time taken by this algorithm. Generally, the larger the value of m, the longer the algorithm will take to run as it has more data to process.

2. What is the significance of p in relation to the time taken by this algorithm?

P, which represents the number of processors or cores used to run the algorithm, plays a crucial role in determining the time taken. With more processors, the algorithm can be divided into smaller tasks and run simultaneously, resulting in a faster execution time.

3. How does the time taken for addition operations (t_add) affect the overall time of the algorithm?

The time taken for addition operations, t_add, is an important factor in determining the overall time of the algorithm. If the algorithm involves a large number of addition operations, the time taken for t_add will significantly impact the overall time of the algorithm.

4. What is the significance of t_s in relation to the time taken by this algorithm?

T_s, which represents the time taken for sorting operations, is a crucial factor in the overall time of the algorithm. If the algorithm involves sorting large amounts of data, t_s will have a significant impact on the overall time taken.

5. How does the value of t_w affect the time taken by this algorithm?

The value of t_w, which represents the time taken for waiting or idle time, can have a significant impact on the overall time of the algorithm. If there is a lot of idle time during the execution of the algorithm, it will result in a longer overall time.

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