Tips to improve Android performance: serializable, view holder pattern, asyntask, threadpool, ...

1. Android performance
Huỳnh Quang Thảo
Silicon Straits Saigon
Google Developer Expert on Android

2. 10 tips to become

3. 10 tips to become
Small

4. 10 tips to become
Small
Easy to apply

5. 10 tips to become
Small
Easy to apply
become …

6. Tip 1: Avoid Serialization
• Pass data between androic components
• Serialize data before persisting to disk/network …

10. Tip 1: implement parcelable
Serialization is slow because using java reKlection
Parcelable is faster with little effort

11. Tip 1: implement parcelable
Serialization is slow because using java reKlection
Parcelable is faster with little effort
Parcelable is extremely faster with some effort

18. Tip 1: Parcelable generator
generate again when changing Kields

19. Tip 1: Other libraries
Google Protobuf
Google Flatbuffer

20. Tip 2: Avoid internal getter/setter
•Without JIT, direct Kield access is 3x faster than getter/setter
•With JIT, direct Kield access is 7x faster than getter/setter

21. Tip 2: Avoid internal getter/setter
•Without JIT, direct Kield access is 3x faster than getter/setter
•With JIT, direct Kield access is 7x faster than getter/setter

22. Tip 3: Avoid using enum
- Code size overhead: One enum requires 13x memory more
than int version.
- Runtime overhead:
- Cost 12-16 bytes for one enum.
- Cost about 20+ bytes for each object in one enum.
Reference: https://www.youtube.com/watch?v=Hzs6OBcvNQE

23. Tip 3: Using @IntDef

25. Tip 4: View Holder Pattern

30. Tip 4: Using RecycleView

31. Tip 4: Using RecycleView

32. Tip 4: Using RecycleView

33. Tip 5: Carefully Dependency Injection
•Guice/ Roboguice: run-time dependency injection framework.
•Dagger: Compile-time dependency injection framework.

34. Tip 5: Carefully Dependency Injection
•Guice/ Roboguice: run-time dependency injection framework.

35. Tip 6: Prefer for-index
for index

36. Tip 6: Prefer for-index
for index
for iterator

37. Tip 6: Prefer for-index
for index
for iterator
for simple

38. Tip 6: Prefer for-index
for index ArrayList 2603
for index Vector 4664
for Simple ArrayList 5133
iterator ArrayList 5142
Iterator vector 11778
for simple vector 11783
•Davik 4.4.4
•list contains 400,000 random integers
•list is walked through 10 times
•Min and max time are thrown out. get average the rest

39. Tip 7: Aware Autoboxing
boolean 8 bits
int 32 bits
Kloat 32 bits
long 64 bits
boolean java.lang.Boolean
int java.lang.Integer
Kloat java.lang.Float
long java.lang.Long

40. Tip 7: Aware Autoboxing

41. Tip 7: Aware Autoboxing

42. Tip 7: Aware Autoboxing

43. Tip 7: Aware Autoboxing

44. Tip 7: Aware Autoboxing

45. Tip 7: Aware Autoboxing
84 new objects
(16x84)

47. HashMap <obj, obj>
SpareBoolMap <bool, obj>
SpareIntMap <int, obj>
SpareLongMap <long, obj>

48. Tip 8: Using Strict Mode

49. Tip 9: Threading model

50. Tip 9: HandlerThread

51. Tip 9: Asynctask

52. Tip 9: Asynctask
•get off UI-work

53. Tip 9: Asynctask
•get off UI-work
•execute serial

54. Tip 9: Threadpool

55. Tip 9: Threadpool

56. Tip 9: IntentService
• is service

57. Tip 9: IntentService
• is service
• all tasks will put into
queue

58. Tip 9: IntentService
• is service
• all tasks will put into
queue
• don’t need to implement
looper, handler …

59. Tip 9: IntentService
• is service
• all tasks will put into
queue
• don’t need to implement
looper, handler …
• thread-safe

60. Tip 10: Control memory heap size

61. Tip 10: Control memory heap size
Android VM limits memory allocation for each application

62. Tip 10: Control memory heap size
Android VM limits memory allocation for each application
Android VM limits memory allocation for each process

63. Java Heap
• The Java Heap is managed by Garbage Collector

64. Java Heap
• Increase memory allocation by creating different process

65. Java Heap
• Increase memory allocation by allowing large heap allocation

66. Native Heap
• Native heap is managed by programmer.
• Native heap is allocated and deallocated manually

70. Ashmem
• Ashmem: Android shared memory
• Allow processes share memory and can be reclaimed
automatically in future

71. Does it matter
• Performance dept.

72. Does it matter
• Performance dept.
• keep code clean is better

73. Does it matter
• Performance dept.
• keep code clean is better
• beware micro optimization. must proKile code

74. ProKile code
• Allways proKile code for checking performance

75. GPU Renderer

76. Systrace

77. Memory viewer

78. Thanks for listening