The document discusses erasure coding in Ceph, which allows storing 3 petabytes of data using only 1.3 petabytes of storage space. Erasure coding saves space compared to replication but makes object mutations and recovery harder. The document also mentions plans to refactor erasure coding in Ceph and test with alpha users, with the goal of completing the work by February 2014. It provides contact information for the lead developer on erasure coding in Ceph.

1. Erasure Code in Ceph

2. Save Space

3. XOR

4. 3 peta => 1.3 peta

5. Harder object mutations / recovery

6. Simple operations and tiering
Replicated
Erasure Coded

7. Promoted to replica on read
Replicated
Erasure Coded

8. Sam & David : refactor

9. Andreas & Loic : erasure code

10. Target : February 2014

11. Why save space before shortage ?

12. Alpha testers

13. Sponsors and developers

14. loic@dachary.org
Artwork GPLv3+ Tartaruga Feliz