Project Update 1

Hello everyone,

So it has been a long time since I first enroll in this course. I have been able to learn alot of things about software and how it compiled as general. For this course, I will need to choose a project to work with. After a while, I decided to go with json-c, because I have always wanted to work with C language, which is why I choose this project to further improve my skill.

After cloned the project on github with a command so that I can work on it freely.

[haung1@xerxes ~]$  git clone https://github.com/json-c/json-c.git
Cloning into 'json-c'...
remote: Enumerating objects: 121, done.
remote: Counting objects: 100% (121/121), done.
remote: Compressing objects: 100% (83/83), done.
remote: Total 3956 (delta 60), reused 78 (delta 38), pack-reused 3835
Receiving objects: 100% (3956/3956), 2.91 MiB | 13.43 MiB/s, done.
Resolving deltas: 100% (2545/2545), done.

And then created a branch so that it does not mess with the original branch, built the project with the help of the github page, I began to benchmark the app on AArch64 systems with a make test command with CMake.

[haung1@xerxes build-test]$ make test
Running tests...
Test project /home/haung1/json-c/build-test
      Start  1: test1
 1/21 Test  #1: test1 ............................   Passed    1.54 sec
      Start  2: test2
 2/21 Test  #2: test2 ............................   Passed    1.41 sec
      Start  3: test4
 3/21 Test  #3: test4 ............................   Passed    0.26 sec
      Start  4: testReplaceExisting
 4/21 Test  #4: testReplaceExisting ..............   Passed    0.23 sec
      Start  5: test_cast
 5/21 Test  #5: test_cast ........................   Passed    0.28 sec
      Start  6: test_charcase
 6/21 Test  #6: test_charcase ....................   Passed    0.22 sec
      Start  7: test_compare
 7/21 Test  #7: test_compare .....................   Passed    0.23 sec
      Start  8: test_deep_copy
 8/21 Test  #8: test_deep_copy ...................   Passed    0.27 sec
      Start  9: test_double_serializer
 9/21 Test  #9: test_double_serializer ...........   Passed    0.23 sec
      Start 10: test_float
10/21 Test #10: test_float .......................   Passed    0.24 sec
      Start 11: test_int_add
11/21 Test #11: test_int_add .....................   Passed    0.20 sec
      Start 12: test_json_pointer
12/21 Test #12: test_json_pointer ................   Passed    0.28 sec
      Start 13: test_locale
13/21 Test #13: test_locale ......................   Passed    0.28 sec
      Start 14: test_null
14/21 Test #14: test_null ........................   Passed    0.22 sec
      Start 15: test_parse
15/21 Test #15: test_parse .......................   Passed    0.28 sec
      Start 16: test_parse_int64
16/21 Test #16: test_parse_int64 .................   Passed    0.22 sec
      Start 17: test_printbuf
17/21 Test #17: test_printbuf ....................   Passed    0.22 sec
      Start 18: test_set_serializer
18/21 Test #18: test_set_serializer ..............   Passed    0.23 sec
      Start 19: test_set_value
19/21 Test #19: test_set_value ...................   Passed    0.20 sec
      Start 20: test_util_file
20/21 Test #20: test_util_file ...................   Passed    0.26 sec
      Start 21: test_visit
21/21 Test #21: test_visit .......................   Passed    0.27 sec

100% tests passed, 0 tests failed out of 21

Total Test time (real) =   7.58 sec

After running, I saw that test1 and test2 are 2 file that took the most time to run, means I will focus on optimizing them first. I see that I can improve this application in multiple of ways, which is:

• Altered build options:
  I may try some compiler options like -g or -o3 depending on my process, I will adjust it properly.
• Code changes to permit better optimization by the compiler and Algorithm improvements: To reduce the runtime and optimize the code, I will apply hoisting, inlining and try strength reduction also for some loop in the code. Even though the owner has already optimized it quite well, I think I can improve it more to give a better runtime. After learning all the techniques in SPO600 course, I believe I can apply my knowledge in this project to improve it.

As I have stated in the beginning, I will try all of my experiment in a different branch to ensure safety. And I will test my code multiple times, compare the original code with mine, make sure the result is not different except for the runtime and more optimize to make it trustworthy. I will update more in my next post. Thank you for reading.