The Quantum Physics of Java
3 likes1,080 views
The document discusses the interplay between quantum physics and Java programming, including various code snippets and performance metrics related to CPU and memory usage. It illustrates how different coding approaches impact execution times and relates computational strategies to computer architecture elements like caches and memory hierarchies. Additionally, it touches on theoretical concepts such as search algorithms and concurrent execution in multi-threaded environments.
![for (int i = 0; i < n; i++) {
a[i] *= 3;
}
for (int i = 0; i < n; i+=16) {
a[i] *= 3;
} 26,1 ms
25,8 ms](https://image.slidesharecdn.com/quantumphysicsofjavajavaland-140331161356-phpapp01/85/The-Quantum-Physics-of-Java-2-320.jpg)
![Michael Heinrichs
http://blog.netopyr.com
@net0pyr
canoo
delivering end-user happiness[ ]](https://image.slidesharecdn.com/quantumphysicsofjavajavaland-140331161356-phpapp01/85/The-Quantum-Physics-of-Java-3-320.jpg)
![for (int i = 0; i < n; i++) {
a[i] *= 3;
}
for (int i = 0; i < n; i+=16) {
a[i] *= 3;
} 26,1 ms
25,8 ms](https://image.slidesharecdn.com/quantumphysicsofjavajavaland-140331161356-phpapp01/85/The-Quantum-Physics-of-Java-4-320.jpg)
![for (int i = 0; i < n; i++) {
a[i % a.length] *= 3;
}](https://image.slidesharecdn.com/quantumphysicsofjavajavaland-140331161356-phpapp01/85/The-Quantum-Physics-of-Java-24-320.jpg)
![for (int i = 0; i < n; i++) {
a[i % a.length] *= 3;
}
for (int i = 0; i < n; i++) {
a[rnd()] *= 3;
}](https://image.slidesharecdn.com/quantumphysicsofjavajavaland-140331161356-phpapp01/85/The-Quantum-Physics-of-Java-31-320.jpg)
![Given: sorted int[16]
Linear or Binary Search?
21,8 ns 28,2 ns](https://image.slidesharecdn.com/quantumphysicsofjavajavaland-140331161356-phpapp01/85/The-Quantum-Physics-of-Java-61-320.jpg)
The Quantum Physics of Java
- 1. The Quantum Physics of Java Michael Heinrichs Canoo Engineering AG
- 2. for (int i = 0; i < n; i++) { a[i] *= 3; } for (int i = 0; i < n; i+=16) { a[i] *= 3; } 26,1 ms 25,8 ms
- 3. Michael Heinrichs http://blog.netopyr.com @net0pyr canoo delivering end-user happiness[ ]
- 4. for (int i = 0; i < n; i++) { a[i] *= 3; } for (int i = 0; i < n; i+=16) { a[i] *= 3; } 26,1 ms 25,8 ms
- 6. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 CPU
- 7. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
- 8. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3
- 9. CPU 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3
- 10. CPU 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
- 11. CPU 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3
- 12. CPU 3 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3
- 13. 1980 1985 1990 1995 2000 2005 2010 1 10 100 1000 10000 100000 CPU Memory Year Performance
- 14. Main Memory CPU
- 16. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 CPU
- 17. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 CPU
- 18. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
- 19. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3
- 20. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 3
- 21. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 1
- 22. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 3
- 23. CPU 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 3 1 1 1 1 3
- 24. for (int i = 0; i < n; i++) { a[i % a.length] *= 3; }
- 25. 1 KB 2 KB 4 KB 8 KB 16 KB 32 KB 64 KB 128 KB 256 KB 512 KB 1 MB 2 MB 4 MB 8 MB 16 MB 32 MB 64 MB 128 MB 256 MB 0 1 2 3 4 5 6 7
- 27. Main Memory L1 Cache L2 Cache L3 Cache CPU
- 28. 1 KB 2 KB 4 KB 8 KB 16 KB 32 KB 64 KB 128 KB 256 KB 512 KB 1 MB 2 MB 4 MB 8 MB 16 MB 32 MB 64 MB 128 MB 256 MB 0 1 2 3 4 5 6 7
- 29. Not quite pints By radioedit (CC BY-SA 2.0)
- 30. Main Memory L1 Cache L2 Cache L3 Cache < 1 ns, 32 KB 7 ns, 256 KB 25 ns, 8 MB 100 ns, 16 GB CPU
- 31. for (int i = 0; i < n; i++) { a[i % a.length] *= 3; } for (int i = 0; i < n; i++) { a[rnd()] *= 3; }
- 32. 1 KB 2 KB 4 KB 8 KB 16 KB 32 KB 64 KB 128 KB 256 KB 512 KB 1 MB 2 MB 4 MB 8 MB 16 MB 32 MB 64 MB 128 MB 256 MB 0 1 2 3 4 5 6 7
- 33. 1 KB 2 KB 4 KB 8 KB 16 KB 32 KB 64 KB 128 KB 256 KB 512 KB 1 MB 2 MB 4 MB 8 MB 16 MB 32 MB 64 MB 128 MB 256 MB 0 5 10 15 20 25
- 34. 1 KB 2 KB 4 KB 8 KB 16 KB 32 KB 64 KB 128 KB 256 KB 512 KB 1 MB 2 MB 4 MB 8 MB 16 MB 32 MB 64 MB 128 MB 256 MB 0 5 10 15 20 25
- 35. perf
- 37. perf stat -p 1234 sleep 5
- 40. Main Memory L1 Cache L2 Cache L3 Cache CPU
- 41. 1 1 1 1 1 11 1 1 1 11 1 1 1 1 CPU
- 42. 1 1 1 1 1 11 1 1 1 11 1 1 1 1 1 1 1 1 CPU
- 43. CPU 1 1 1 1 1 11 1 1 1 11 1 1 1 1 1 1 1 1 1
- 44. CPU 1 1 1 1 1 11 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1
- 45. 1 KB 2 KB 4 KB 8 KB 16 KB 32 KB 64 KB 128 KB 256 KB 512 KB 1 MB 2 MB 4 MB 8 MB 16 MB 32 MB 64 MB 128 MB 256 MB 0 5 10 15 20 25
- 46. int a; Thread 1: a++; Thread 2: return a; 2,1 ops/ns 1,2 ops/ns
- 47. Main Memory L2 Cache L3 Cache L1 Cache L1 Cache Core 1 Core 2
- 48. L1 Cache L1 Cachea Core 1 Core 2
- 49. L1 Cache L1 Cachea a ? Core 1 Core 2
- 57. L1 Cache L1 Cachea a Core 1 Core 2
- 58. int a; int b; Thread 1: a++; Thread 2: return b; 2,1 ops/ns 1,2 ops/ns
- 59. L1 Cache L1 Cachea b Core 1 Core 2
- 60. L1 Cache L1 Cachea ab b Core 1 Core 2
- 61. Given: sorted int[16] Linear or Binary Search? 21,8 ns 28,2 ns
- 63. A B C D E CPU
- 67. Fetch Decode Execute Write- back A A B C D E
- 68. Fetch Decode Execute Write- back A A B C D E
- 69. Fetch Decode Execute Write- back B A B C D E A
- 70. Fetch Decode Execute Write- back C A B C D E B A
- 71. Fetch Decode Execute Write- back D A B C D E C B A
- 72. Fetch Decode Execute Write- back E A B C D E D C B
- 73. Fetch Decode Execute Write- back A B C D E
- 74. Fetch Decode Execute Write- back A B C D E A
- 75. Fetch Decode Execute Write- back A B C D E A?
- 76. Fetch Decode Execute Write- back A B C D E AB
- 77. Fetch Decode Execute Write- back A B C D E C B A
- 78. Fetch Decode Execute Write- back A B C D E C B A
- 79. Fetch Decode Execute Write- back A B C D E C B A
- 80. Fetch Decode Execute Write- back A B C D E AE
- 81. Binary Search while (low <= high) … if (midVal < needle) … else if (midVal > needle) … else …
- 82. Linear Search for element : haystack if element == needle … else if (element > needle) …
- 83. int a; int b; a *= 3; a *= 5; a *= 3; b *= 5; 2,3 ns 2,1 ns
- 85. Fetch Decode Execute Write- back
- 86. Fetch Decode Execute Write- back Execute Execute
- 87. Fetch Decode Execute Write- back Execute Execute Fetch Fetch
- 90. Fetch Decode Write- back Fetch Fetch A B C A B C Execute Execute Execute
- 91. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C A B C
- 92. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C A B C
- 93. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C A B C
- 94. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C AB C
- 95. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C B C
- 96. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C C
- 97. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C C
- 98. Fetch Decode Execute Write- back Execute Execute Fetch Fetch A B C
- 99. a *= 3 a *= 5 a *= 3 b *= 5 int a; int b; a *= 3; a *= 5; a *= 3; b *= 5;
- 100. Know thy CPU (because sometimes it matters)
- 101. This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/4.0/ or send a letter to Creative Commons, 444 Castro Street, Suite 900, Mountain View, California, 94041, USA.