optimization/REPORT.TXT at master · janamano/optimization · GitHub

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CSC C85 - Lab 3 - Code Optimization
_______________________________________________________________________

Team name:

Name 1 (last, first):De Costa, Kalindu
Student number 1:1001392619

Name 2 (last, first):Manoharan, Janarthanan
Student number 2:1001291657

If applicable:
Name 3 (last, first):
Student number 3:

(Special: Lose marks for failing to complete the above)
_______________________________________________________________________

Questions:

0) On the same computer, and with no other applications open:

   - Run vanilla version, compiled as per the compile script (no compiler
     optimization) and list: Vanilla (no compiler opt) FPS = 4.3

   - Run your optimized code, compiled without compiler optimization
     and list: Your Code (no compiler opt) FPS = 8.2

   - Run vanilla code compiled with flag -O3 for compiler optimization
     and list: Vanilla (compiler optimized) FPS =9.3

   - Run your optimized code, compiled with flag -O3
     and list: Your Code (compiler optimized) FPS =11.9

     What is the ratio of your code (compiler optimized) to vanilla
     with no compiler optimization?

     Ratio = Vanilla(no compiler opt) FPS / Your code(compiler optimized) FPS
           =4.3/11.9 = 0.3613

a) Look at the profiler output for vanilla_imageRescale(). Identify the
   lines that you think are un-necessary bottlenecks (i.e. lines whose
   CPU usage can be reduced or eliminated by careful coding).

   List these bottleneck lines in descending order (i.e. the ones that
   consume most time at the top) of CPU time. Please list
	- The actual line of code
	- The amount of time taken
	(you can copy/paste from the profiler output)

   For each line, explain why the line creates a bottleneck (in terms
   of what you know about CPU architecture). I want specific reasons
   why a line you listed takes a large chunk of CPU time.

b) For each of the lines in a)

   Describe what you did in fast_imageRescale() to reduce/resolve the
   problem.

   Explain why your improvement should work (again, based on what you
   know about CPU architecture).

c) List any other optimizations you performed in your code and why they
   help increase speed

d) Is there any part of the vanilla code that could not be optimized
   at all? if so, which?

e) Do you think you have achieved close to optimal performance on this
   code? (yes/no)

f) If your answer to d) is no, what could you do to further increase
   performance?

______________________________________________________________________

Grading

Attending lab and working hard -         	 	/10

Programming exercise
	- Competitive performance of your code	 	/70
             Your FPS multiplier:     (Max:  )

Answers in this report					/20

Penalty marks (TA assigned)

Total for First Lab Session:			   	/100 (*)

(*) This mark is conditional to all team members being able to explain
    any part of the work when questioned.