Garbage? Garbage? GAAAAAARRRBAAAAGGEEEE

A brief talk about Garbage Collection and the implications of the new RGenGC proposal.

Transcript

1. Garbage? Garbage? GARRRRRBAAAAAAGG GGEEEEEEE mrb / lightning talks @ pp / May 3, 2013
2. I Like Garbage
3. I Like Thinking About Garbage
4. I Like Thinking About Looking For Garbage
6. What is Garbage Collection?
7. Automatic memory management for your computer programs.
8. ( )
10. “Living” vs. “Dead”
11. What memory are you using, and what memory can be reclaimed?
12. Your objects form a graph.
13. Traversing graphs is hard.
14. The Big Algorithms • Mark and Sweep • Reference Counting • Generational
15. Ruby makes a lot of garbage.
16. Ruby’s Garbage Story https://bugs.ruby-lang.org/issues/8339 https://bugs.ruby-lang.org/attachments/3686/gc-strategy- en.pdf
17. Ruby’s Current GC • Mark And Sweep • Conservative • Bitmap Marking • Non-Recursive Marking • No Moving • Favors C Extensions
18. Rubyists wrote C extensions to make certain Ruby code run faster.
19. The primitive Garbage Collector supports these C extensions.
20. Now, this same Garbage Collector is what is preventing Ruby code from being as fast as it could be.
21. “Despite the best efforts of Koichi and other contributors, Ruby Core's concern with backwards compatibility (particularly regarding the C Extension API) keeps MRI lagging more than a decade behind Ruby implementations like Rubinius and JRuby which already have precise, generational and incremental garbage collectors.” - Vincent Marti (@vmg) https://github.com/blog/1489-hey-judy-don-t-make-it-bad
22. RGenGC Is... • An awesome, fearless hack • Likely to make some Ruby code run faster • Certain to not break compatibility with C extensions • Progress
23. RGenGC Isn’t... • The answer to Ruby’s problems • Likely to make all Ruby code faster in the long run • Going to draw people to Ruby • Limitless Progress
24. In Conclusion • We need to figure this out • We can find a way forward
25. Thanks!