Thread Profiling in Python

How to create your own statistical thread profiler in Python language.

Transcript

1. @amjithr THREAD PROFILING DJANGOCON EU ▪ Wednesday, May 15, 13
2. @amjithr Hi  Wednesday, May 15, 13
3. @amjithr ♥ Wednesday, May 15, 13
4. Wednesday, May 15, 13
5. @amjithr PERFORMANCE! Wednesday, May 15, 13
6. @amjithr WHAT’S PROFILING? Wednesday, May 15, 13
7. @amjithr WHAT’S PROFILING? Measuring Performance Wednesday, May 15, 13
8. @amjithr cPROFILE Wednesday, May 15, 13
9. @amjithr $ python -m cProfile lcm.py 7780242 function calls in 3.822 seconds Ordered by: standard name ncalls tottime percall cumtime percall filename:lineno(function) 1 0.000 0.000 3.822 3.822 lcm.py:12(<module>) 1 2.383 2.383 3.822 3.822 lcm.py:12(lcm) 3890120 0.724 0.000 0.724 0.000 {max} 1 0.000 0.000 0.000 0.000 {method 'disable' of 3890119 0.716 0.000 0.716 0.000 {min} Wednesday, May 15, 13
10. @amjithr $ python -m cProfile shorten.py 88466 function calls (86374 primitive calls) in 0.220 seconds Ordered by: standard name ncalls tottime percall cumtime percall filename:lineno(function) 1 0.000 0.000 0.000 0.000 <string>:1(<lambda>) 1 0.000 0.000 0.000 0.000 <string>:1(<module>) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedCTE) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedCase) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedCast) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedClauseElement) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedClauseList) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedColumn) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedColumnClause) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedColumnElement) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedCompoundSelect) 1 0.000 0.000 0.000 0.000 <string>:1(AnnotatedDelete) .... .... ..... ..... .... ...... .... .... ..... ..... .... ...... Wednesday, May 15, 13
11. @amjithr  RunSnakeRun Wednesday, May 15, 13
12. @amjithr Wednesday, May 15, 13
13. @amjithr $ time python fib.py python fib.py 5.43s user 0.01s system 99% cpu 5.451 total $ time python -m cProfile fib.py python -m cProfile fib.py 9.63s user 0.04s system 99% cpu 9.670 total Wednesday, May 15, 13
14. @amjithr $ time python fib.py python fib.py 5.43s user 0.01s system 99% cpu 5.451 total $ time python -m cProfile fib.py python -m cProfile fib.py 9.63s user 0.04s system 99% cpu 9.670 total ~ % OVERHEAD Wednesday, May 15, 13
15. @amjithr You can’t run it in production Wednesday, May 15, 13
16. @amjithr PROFILER IN PRODUCTION Wednesday, May 15, 13
17. @amjithr SLOW PRODUCTION NOT REALISTIC cProfile Wednesday, May 15, 13
18. @amjithr CRITICAL FUNCTIONS HYBRID PROFILING TARGETED PROFILING Wednesday, May 15, 13
19. @amjithr WEB FRAMEWORKS VIEW HANDLERS SQL CALLS TARGET Wednesday, May 15, 13
20. @amjithr TRANSACTION TRACE Wednesday, May 15, 13
21. @amjithr NON-INSTRUMENTED CODE Wednesday, May 15, 13
22. @amjithr Cool Story, Bro! Can we talk about statistical profilers? Wednesday, May 15, 13
23. @amjithr STATISTICAL THREAD PROFILER Wednesday, May 15, 13
24. @amjithr Wednesday, May 15, 13
25. @amjithr WAT? Wednesday, May 15, 13
26. @amjithr OVERLY ATTACHED Wednesday, May 15, 13
27. @amjithr OVERLY ATTACHED Interrupt Inquire Collate Wednesday, May 15, 13
28. @amjithr OVERLY ATTACHED Interrupt Inquire Collate Wednesday, May 15, 13
29. @amjithr OVERLY ATTACHED  Interrupt Inquire Collate Wednesday, May 15, 13
30. @amjithr OVERLY ATTACHED  ◴ Interrupt Inquire Collate Wednesday, May 15, 13
31. @amjithr  ◴ Interrupt Inquire Collate STATISTICAL PROFILER Wednesday, May 15, 13
32. @amjithr Wednesday, May 15, 13
33. @amjithr SIGNALS THREADS INTERRUPT Wednesday, May 15, 13
34. @amjithr HTTP://FLIC.KR/P/bE NXH SIGNALS Wednesday, May 15, 13
35. @amjithr import signal # Use the virtual timer sig = signal.ITIMER_VIRTUAL # register a handler signal.signal(sig, handler) # 100ms repeating timer signal.setitimer(sig, 0.1, 0.1) SIGNAL Wednesday, May 15, 13
36. @amjithr PROs CONs Accurate timer Unix only - Ignored in mod_wsgi - Can’t interrupt C-extensions SIGNAL Wednesday, May 15, 13
37. @amjithr HTTP://FLIC.KR/P/db ZS THREADS Wednesday, May 15, 13
38. @amjithr import threading # Create a background thread t = threading.Thread(target=handler) t.setDaemon(True) # Start the thread t.start() # Sleep for 100ms in handler time.sleep(0.1) THREAD Wednesday, May 15, 13
39. @amjithr PROs CONs Cross Platform Inaccurate for CPU tasks mod_wsgi compatible Can’t interrupt C-extensions THREAD Wednesday, May 15, 13
40. @amjithr INQUIRE Stack frame of every thread Wednesday, May 15, 13
41. @amjithr >>> import sys # Get stack frames of every thread >>> frames = sys._current_frames() # Dictionary of { thread_id: frame_obj } >>> frames {4420: <frame object at 0x7fd96c04a650>, 1407: <frame object at 0x7fd96c301730>} INQUIRE Wednesday, May 15, 13
42. @amjithr function3 function2 function1 FRAMES Wednesday, May 15, 13
43. @amjithr function3 function2 function1 Fn Name File Name Line No Arguments Globals Locals ... FRAMES Wednesday, May 15, 13
44. @amjithr function3 function2 function1 Fn Name File Name Line No Arguments Globals Locals ... FRAMES Wednesday, May 15, 13
45. @amjithr >>> import traceback # Extract useful info from frame >>> traceback.extract_stack(frame) [('code.py', 88, 'runsource', 'return'), ('code.py', 110, 'runcode', 'print')] EXTRACT Wednesday, May 15, 13
46. @amjithr COLLATE Wednesday, May 15, 13
47. @amjithr Default Dictionary ATTEMPT Wednesday, May 15, 13
48. @amjithr Default Dictionary Uniquely identify a function fdata = (f_name, file, line) Build a dictionary calls = defaultdict(int) Increment the value when found in frames calls[fn_a] += 1 ATTEMPT Wednesday, May 15, 13
49. @amjithr Default Dictionary Uniquely identify a function fdata = (f_name, file, line) Build a dictionary calls = defaultdict(int) Increment the value when found in frames calls[fn_a] += 1 ATTEMPT Wednesday, May 15, 13
50. @amjithr Default Dictionary Uniquely identify a function fdata = (f_name, file, line) Build a dictionary calls = defaultdict(int) Increment the value when found in frames calls[fn_a] += 1 ATTEMPT Wednesday, May 15, 13
51. @amjithr Results fn_a=3 fn_b=4 fn_c=5 fn_d=1 { } ATTEMPT Wednesday, May 15, 13
52. @amjithr Simple to implement Identifies hot functions No context ATTEMPT Wednesday, May 15, 13
53. @amjithr Call Tree ATTEMPT Wednesday, May 15, 13
54. @amjithr Example T1 Wednesday, May 15, 13
55. @amjithr Example fn_a fn_b fn_c T1 Wednesday, May 15, 13
56. @amjithr Example fn_a fn_b fn_c T1 Wednesday, May 15, 13
57. @amjithr Example fn_a fn_b fn_c T1 fn_a=1 Wednesday, May 15, 13
58. @amjithr Example fn_a fn_b fn_c T1 fn_a=1 Wednesday, May 15, 13
59. @amjithr Example fn_a fn_b fn_c T1 fn_a=1 fn_b=1 Wednesday, May 15, 13
60. @amjithr Example fn_a fn_b fn_c T1 fn_a=1 fn_b=1 Wednesday, May 15, 13
61. @amjithr Example fn_a fn_b fn_c T1 fn_a=1 fn_b=1 fn_c=1 Wednesday, May 15, 13
62. @amjithr T2 fn_a=1 fn_b=1 fn_c=1 Example Wednesday, May 15, 13
63. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_c=1 Example Wednesday, May 15, 13
64. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_c=1 Example Wednesday, May 15, 13
65. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_c=1 fn_a=2 Example Wednesday, May 15, 13
66. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_c=1 fn_a=2 Example Wednesday, May 15, 13
67. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_c=1 fn_a=2 fn_b=2 Example Wednesday, May 15, 13
68. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_c=1 fn_a=2 fn_b=2 Example Wednesday, May 15, 13
69. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_a=2 fn_b=2 fn_c=1 Example Wednesday, May 15, 13
70. @amjithr fn_a fn_b fn_d T2 fn_a=1 fn_b=1 fn_a=2 fn_b=2 fn_c=1 fn_d=1 Example Wednesday, May 15, 13
71. @amjithr fn_a=1 fn_a=2 fn_b=2 fn_c=1 fn_d=1 T3 Example Wednesday, May 15, 13
72. @amjithr fn_a fn_d fn_a=1 fn_a=2 fn_b=2 fn_c=1 fn_d=1 T3 Example Wednesday, May 15, 13
73. @amjithr fn_a fn_d fn_a=1 fn_a=2 fn_b=2 fn_c=1 fn_d=1 T3 Example Wednesday, May 15, 13
74. @amjithr fn_a fn_d fn_a=1 fn_a=2 fn_b=2 fn_c=1 fn_d=1 fn_a=3 T3 Example Wednesday, May 15, 13
75. @amjithr fn_a fn_d fn_a=1 fn_a=2 fn_b=2 fn_c=1 fn_d=1 fn_a=3 T3 Example Wednesday, May 15, 13
76. @amjithr fn_a fn_d fn_a=1 fn_a=2 fn_a=3 fn_b=2 fn_c=1 fn_d=1 T3 Example Wednesday, May 15, 13
77. @amjithr fn_a fn_d fn_a=1 fn_a=2 fn_a=3 fn_b=2 fn_c=1 fn_d=1 fn_d=1 T3 Example Wednesday, May 15, 13
78. @amjithr EXISTING TOOLS Wednesday, May 15, 13
79. @amjithr http://pypi.python.org/pypi/statprof StatProf Signals CLI Wednesday, May 15, 13
80. @amjithr https://github.com/bdarnell/plop PLOP Signals D Call Graph Wednesday, May 15, 13
81. @amjithr Wednesday, May 15, 13
82. @amjithr NewRelic Threads GUI Wednesday, May 15, 13
83. @amjithr Wednesday, May 15, 13
84. @amjithr SUMMARY Features Limitations Low Overhead No green threads CPython & PyPy No Jython support Wednesday, May 15, 13
85. @amjithr WRONG USE OF MEME. WHO LET THIS GUY ON THE STAGE? PROFILER in PRODUCTION Wednesday, May 15, 13
86. @amjithr FINALE DETERMINISTIC + STATISTICAL Wednesday, May 15, 13
87. @amjithr X-Ray Sessions Wednesday, May 15, 13
88. @amjithr DETERMINISTIC Wednesday, May 15, 13
89. @amjithr STATISTICAL Wednesday, May 15, 13
90. @amjithr HISTOGRAM Wednesday, May 15, 13
91. @amjithr RESPONSE & THROUGHPUT Wednesday, May 15, 13
92. @amjithr THANK YOU! @amjithr Wednesday, May 15, 13
93. Questions? • Promo: newrelic.com/djangocon • 30 days of Pro. • Free T-shirt. • In-depth data. Wednesday, May 15, 13