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'''5''' Look over the report, and propose 3 leaf-functions (functions that do not call other functions) for offloading towards a coprocessor. Write the reason for choosing each of them, and how much is gained by offloading them. Assume coprocessor works at infinite clock, but data is transferred at 200 MB/s. Hint: use the callgraph (by installing the graphiviz package). Keep a snapshot with the analysis report as proof. Send result and snapshot(s) to the teacher. | '''5''' Look over the report, and propose 3 leaf-functions (functions that do not call other functions) for offloading towards a coprocessor. Write the reason for choosing each of them, and how much is gained by offloading them. Assume coprocessor works at infinite clock, but data is transferred at 200 MB/s. Hint: use the callgraph (by installing the graphiviz package). Keep a snapshot with the analysis report as proof. Send result and snapshot(s) to the teacher. | ||
| + | '''6''' | ||
| + | 10 / 10 points for identifying 3 most-heavy leaf-functions and correct (within 10%) computation for offloading impact. | ||
| + | 9 / 10 points for identifying 3 most-heavy leaf-functions and correct (within 20%) computation for offloading impact. | ||
| + | 8 / 10 points for identifying 2 most-heavy leaf-functions and correct (within 10%) computation for offloading impact. | ||
| + | 7 / 10 points for identifying 2 most-heavy leaf-functions and correct (within 30%) computation for offloading impact. | ||
| + | 6 / 10 points for identifying 1 most-heavy leaf-functions and correct (within 30%) computation for offloading impact. | ||
| + | 5 / 10 points for identifying 1 most-heavy leaf-functions and correct (within 50%) computation for offloading impact. | ||
'''Note''': Valgrind is also great for checking memory leaks: | '''Note''': Valgrind is also great for checking memory leaks: | ||
Versiunea de la data 14 aprilie 2018 09:03
Session 5
Task: run an open-source profiler (valgrind & gprof or visual studio) and improve performance of keypoint extraction in ASIFT C++ code
1. Download ASIFT project from here: http://www.ipol.im/pub/art/2011/my-asift/
2. Run demo_ASIFT with the two included Adams as input images from the Sixtine Chapel. Horizontal result should look like this: 
3. Modify code to only do "compute_asift_keypoints" (matching is not interesting, since it was covered in the previous session)
4. Run the valgrind profiler
eg, for dummy program:
g++ -std=c++11 dummy.cpp -o dummy (compile program dummy)
valgrind --tool=callgrind ./dummy (run the program with callgrind; generates a file callgrind.out.12345 that can be viewed with kcachegrind)
kcachegrind whateverprofile.callgrind // open profile.callgrind with kcachegrind
5 Look over the report, and propose 3 leaf-functions (functions that do not call other functions) for offloading towards a coprocessor. Write the reason for choosing each of them, and how much is gained by offloading them. Assume coprocessor works at infinite clock, but data is transferred at 200 MB/s. Hint: use the callgraph (by installing the graphiviz package). Keep a snapshot with the analysis report as proof. Send result and snapshot(s) to the teacher.
6 10 / 10 points for identifying 3 most-heavy leaf-functions and correct (within 10%) computation for offloading impact. 9 / 10 points for identifying 3 most-heavy leaf-functions and correct (within 20%) computation for offloading impact. 8 / 10 points for identifying 2 most-heavy leaf-functions and correct (within 10%) computation for offloading impact. 7 / 10 points for identifying 2 most-heavy leaf-functions and correct (within 30%) computation for offloading impact. 6 / 10 points for identifying 1 most-heavy leaf-functions and correct (within 30%) computation for offloading impact. 5 / 10 points for identifying 1 most-heavy leaf-functions and correct (within 50%) computation for offloading impact.
Note: Valgrind is also great for checking memory leaks:
valgrind --leak-check=full <path>
valgrind --tool=memcheck <path>
Points (out of 10) vs. expected performance ():
TBD
