RMagick, migrate to ImageMagick 7 #RubyKaigi #RubyKaigi2019

Transcript

1. RMagick, migrate to ImageMagick 7 Shizuo Fujita
2. self.inspect • @watson1978 • Ubiregi, Inc • Ruby committer • RMagick maintainer
3. What's RMagick
4. "RMagick is an interface between the Ruby programming language and the ImageMagick image processing library."
5. Active members ˏmockdeep ˏwatson1978 ˏdlemstra
6. My Motivation
7. I want to use Ruby ... •Web programming
8. I want to use Ruby ... •Web programming •iOS programming
9. I want to use Ruby ... •Web programming •iOS programming •Image processing
10. I want to use Ruby ... •Web programming •iOS programming •Image processing •Machine learning, etc
11. I want to use Ruby ... •Web programming •iOS programming •Image processing •Machine learning, etc To meet crazy great people at Ruby World
12. Current Status of RMagick
14. Fixed major problems since v2.16.0 •Set up •Memory leaks •SEGVs
15. Set up problems
16. Set up problems •macOS (Homebrew) •Windows
17. macOS (Homebrew)
18. macOS (Homebrew)
19. Windows •Ruby has some environments • MingW • MSWin • Cygwin • Windows Subsystem for Linux
20. Windows •Ruby has some environments • MingW • MSWin • Cygwin • Windows Subsystem for Linux
21. MingW...?
22. Set up : MingW
23. Solution https://github.com/oneclick/rubyinstaller2/wiki/For-gem-developers
24. MingW works
25. MSWin...?
26. Set up : MSWin
27. MSWin supported...? Looks like MSWin supporting code...
28. Not supported... Why !? For MSWin
29. MSWin works well
30. Memory leak
31. Fixed many memory leaks 55 Closed
32. Case 1 VALUE Image_shear(VALUE self, VALUE x_shear, VALUE y_shear) { Image *image, *new_image; ExceptionInfo *exception; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); new_image = ShearImage(image, NUM2DBL(x_shear), NUM2DBL(y_shear), exception); rm_check_exception(exception, new_image, DestroyOnError); (void) DestroyExceptionInfo(exception); rm_ensure_result(new_image); return rm_image_new(new_image); }
33. VALUE Image_shear(VALUE self, VALUE x_shear, VALUE y_shear) { Image *image, *new_image; ExceptionInfo *exception; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); new_image = ShearImage(image, NUM2DBL(x_shear), NUM2DBL(y_shear), exception); rm_check_exception(exception, new_image, DestroyOnError); (void) DestroyExceptionInfo(exception); rm_ensure_result(new_image); return rm_image_new(new_image); } Case 1 Allocate memory
34. VALUE Image_shear(VALUE self, VALUE x_shear, VALUE y_shear) { Image *image, *new_image; ExceptionInfo *exception; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); new_image = ShearImage(image, NUM2DBL(x_shear), NUM2DBL(y_shear), exception); rm_check_exception(exception, new_image, DestroyOnError); (void) DestroyExceptionInfo(exception); rm_ensure_result(new_image); return rm_image_new(new_image); } Case 1 Allocate memory Destroy memory
35. VALUE Image_shear(VALUE self, VALUE x_shear, VALUE y_shear) { Image *image, *new_image; ExceptionInfo *exception; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); new_image = ShearImage(image, NUM2DBL(x_shear), NUM2DBL(y_shear), exception); rm_check_exception(exception, new_image, DestroyOnError); (void) DestroyExceptionInfo(exception); rm_ensure_result(new_image); return rm_image_new(new_image); } Case 1 Allocate memory Destroy memory Raise exception with unexpected value
36. VALUE Image_shear(VALUE self, VALUE x_shear, VALUE y_shear) { Image *image, *new_image; ExceptionInfo *exception; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); new_image = ShearImage(image, NUM2DBL(x_shear), NUM2DBL(y_shear), exception); rm_check_exception(exception, new_image, DestroyOnError); (void) DestroyExceptionInfo(exception); rm_ensure_result(new_image); return rm_image_new(new_image); } Case 1 Allocate memory Destroy memory Raise exception with unexpected value Unreachable by exception
37. Case 1: Exception causes Memory Leak image = Magick::Image.read('sample.png').first begin image.shear('x', 'y') rescue end
38. Case 2 static VALUE has_attribute(VALUE self, MagickBooleanType....[snip]) { Image *image; ExceptionInfo *exception; MagickBooleanType r; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); r = (attr_test)(image, exception); CHECK_EXCEPTION() return r ? Qtrue : Qfalse; }
39. static VALUE has_attribute(VALUE self, MagickBooleanType....[snip]) { Image *image; ExceptionInfo *exception; MagickBooleanType r; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); r = (attr_test)(image, exception); CHECK_EXCEPTION() return r ? Qtrue : Qfalse; } Case 2 Allocate memory
40. static VALUE has_attribute(VALUE self, MagickBooleanType....[snip]) { Image *image; ExceptionInfo *exception; MagickBooleanType r; image = rm_check_destroyed(self); exception = AcquireExceptionInfo(); r = (attr_test)(image, exception); CHECK_EXCEPTION() return r ? Qtrue : Qfalse; } Case 2 Allocate memory Missing destroy
41. Case 2: Missing destroy lead to Memory Leak image = Magick::Image.read('sample.png').first image.gray?
42. Case 3 Unnecessary clone API returns NEW image in allocated memory
43. Case 3: Memory Leak by incorrect API usage image = Magick::Image.read('sample.png').first image.sharpen_channel
44. Case 4
45. Case 4 Found memory leak in ImageMagick
46. Case 4
47. Case 4: Huge software has Memory Leak
48. How to detect memory leak
49. Profiler tool
50. Profiler tool Memory leak detected
51. Profiler tool
52. Profiler tool... •Detects at executed code only •unit-test •RSpec •Needs better coverage...
53. Code reading... •To find same pattern that profiler detects
54. SEGV
55. Closed 5 SEGVs 4 Fixed 1 Workaround
56. Workaround Case Help wanted
57. Workaround Case •Call back image processing progress to Ruby User's Ruby code RMagick ImageMagick Callback
58. ruby_stack_length() shows 51119378542 = 47 GB • Invalid stack length • GC running →SEGV
59. RMagick is better than ever.
60. Future...
61. ImageMagick 7 support
62. Preparing draft code... now
63. Plan 1: Split RMagick ver 4.x RMagick ver 3.x ver 3.0 ver 3.1 ver 2.16.1 ImageMagick 7 ImageMagick 6
64. Plan 2 : Mix both ImageMagick 7 ImageMagick 7 ImageMagick 6 Using many #if defined ...
65. Plan 3: Bundle both ImageMagick 7 ImageMagick 6
66. We welcome good ideas for the future
67. Announcement •RubyData Workshop (Tomorrow, 14:20 ~) •RubyKaigi 2019 Code Party (Tomorrow, 19:00 ~)
68. Thank you