Fall 2006 CS 432/632/732 Parallel Computing
Homework-1
9/12/2006 1-3
PART-I – Individual Work Only. 200 points. Due September 26, 2006.
Using the POSIX threads library implement a multi-threaded version of the image processing
program implemented in Homework-0.
1. Use one-dimensional data distribution, test the program for different threads shown in table
1, note down the time taken, and complete table below.
Table 1. Time taken (in seconds) with one-dimensional data distribution
Image1 Image2 Image3
No. of
threads Mean Median HP
Filter Mean Median HP
Filter Mean Median HP
Filter
Sequential
1
2
4
6
8
10
12
14
16
2. Use two-dimensional data distribution, test the program for different threads shown in table
2, note down the time taken, and complete table below.
Table 2. Time taken (in seconds) with two-dimensional data distribution
Image1 Image2 Image3
No. of
threads Mean Median HP
Filter Mean Median HP
Filter Mean Median HP
Filter
Sequential
1 X 1
1 X 2
1 X 4
2 X 1
2 X 2
2 X 3
3 X 2
3 X 3
3 X 4
4 X 1
4 X 2
4 X 3
4 X 4
3. Analyze the difference in execution time between one- and two-dimensional data distribution
(if any) and provide possible explanations for the difference in execution time.
