Melhorando a performance de testes em Ruby. Nesta talk conto como baixamos de 25 min para 13min um build de 12 mil testes.

1. Optimizing build time
Performance running tests
Jônatas Paganini @jonatasdp

2. test suite

3. RSpec

4. 12K
assertions

5. ~25’
Build time / 3 machines

6. >100’
in localhost

7. MONOLITHIC
APP

8. NOW

9. ~13’
Build time / 4 machines

10. ?

11. Little Changes on
factories

12. girl ?factory

13. Avoid callbacks
Callbacks can be lazy and
unuseful running all the time

14. Model#skip_callback
To avoid run the the hook each factory

15. Coverage?

16. after(:create)
To run it in a specific factory

17. Profiling Associations

18. Specializing
factories

19. Specialized factories

20. Associations
Results

21. Use lazy Associations
Associations naturally invokes their own factories.

22. Avoid factory: for associations
Associations naturally invokes their own factories.

23. association &block

24. association &block

25. quick wins

26. Use build_stubbed
Instead of create

27. hack sign_in
Avoid touch database each login

28. ConfigureRSpec

29. sign_inbuild_stubbed

30. Use stub to avoid
inflateassociations

33. build Instead of create

37. CI Improvements
We use CircleCI
● Split specs by context
● Hack postgres.conf
● Postgresql on Memory

38. Splitspecs by
Context

39. CircleCi divide tests
by time NOT
context

40. SplitSpecs by
DIRECTORY

41. postgres.conf

42. fsync = ’off’

43. full_page_writes = ’off’

44. checkpoint_segments = ’100’
checkpoint_timeout = ’45 min’

45. data_directory = ’/tmp/postgres-on-memory’

46. dir=/tmp/postgresql-on-memory

47. dir=/tmp/postgresql-on-memory
mkdir $dir

48. dir=/tmp/postgresql-on-memory
mkdir $dir
mount -o size=200M,mode=0666 tmpfs $dir

49. dir=/tmp/postgresql-on-memory
mkdir $dir
mount -o size=200M,mode=0666 tmpfs $dir
chown postgres:postgres $dir

50. dir=/tmp/postgresql-on-memory
mkdir $dir
mount -o size=200M,mode=0666 tmpfs $dir
chown postgres:postgres $dir
sudo su - postgres -c
'/usr/lib/postgresql/9.4/bin/initdb
--encoding=UTF8 --pgdata=$dir

51. NEXT LEVEL
<what> run <when>

52. hardcore scenarios
Split Specs

53. Nightly Build

54. if [ -n "${RUN_NIGHTLY_BUILD}" ];
rspec spec/features --tag "~smoke"

55. if [ -n "${RUN_NIGHTLY_BUILD}" ];
rspec spec/features --tag "~smoke"
if [ -z "${RUN_NIGHTLY_BUILD}" ];
rspec spec/features --tag "smoke"

56. http://shipit.resultadosdigitais.com.br/blog
● /ruby-e-rspec-melhorando-a-legibilidade-de-seus-testes/
● /rspec-performance-tips/
● /otimizando-testes-factory-girl-e-rspec/

57. Conclusion
● Avoid touch database
● Avoid callbacks no sense
● Avoid things you don’t need
● Write specialized factories
● Rate (classify) your test
● Benchmark all isolated steps
It’s all about responsibilities

58. Thanks!
@jonatasdp
http://ideia.me
http://shipit.resultadosdigitais.com.br