The document discusses the implementation and benefits of erasure coding in Ceph, focusing on space savings and reliability. It highlights various contributors and advancements made since the code's release in May 2014. Additionally, it mentions performance improvements through specific hardware optimizations and different coding techniques.

1. Erasure Code in Ceph
Loic Dachary @ Red Hat

2. Save Space

3. 5 minutes role playing game

4. XOR

5. 3 peta => 1.3 peta

6. Harder object mutations / recovery

7. Simple operations and tiering
Replicated Erasure Coded

8. Promoted to replica on read
Replicated Erasure Coded

9. Sam & David : internals

10. Janne & Andreas & Loic & Takeshi
erasure code

11. Released May 2014 : Firefly

12. Why save space before shortage ?

13. Reliability Model
● After an OSD is lost
● Recovery
● Backfilling a new OSD

14. April 2015 : Hammer

15. Repair K=10, M=4

16. Locally Recoverable Codes
LRC @ Red Hat

17. SHEC Takeshi @ Fujitsu

18. ISA plugin Yuan @ Intel
SIMD aka SSE2, SSE3, SSE4
Only for Intel processors
~50% Faster

19. jerasure ARM Janne @ ARM

20. Infernalis

21. Hitchhiker Rashmi @ U.C. Berkeley

22. ldachary@redhat.com
Artwork GPLv3+ Tartaruga Feliz