This document discusses using MapReduce with Cassandra. It describes how writing to Cassandra from MapReduce has always been possible, while reading was enabled starting with Cassandra 0.6.x. Using MapReduce with Cassandra provides analytics capabilities and avoids single points of failure compared to MapReduce with HBase. The document covers setup and configuration considerations like locality, and provides examples of a separate cluster approach and hybrid cluster approach. It also outlines future work like improving output to Cassandra and adding Hive support.

1. CASSANDRA
+
HADOOP

2. Two Aspects
MapReduce
Pig

3. MR + Cassandra - History

4. MR + Cassandra - History
Writing to Cassandra - always been possible

5. MR + Cassandra - History
Writing to Cassandra - always been possible
Cassandra 0.6.x enables reading data

6. MR + Cassandra - History
Writing to Cassandra - always been possible
Cassandra 0.6.x enables reading data
Uses its own InputSplit, InputFormat, RecordReader

7. Why MR + Cassandra?
Cassandra is a great data store but what about
analytics? MapReduce!
Arguable win over MapReduce + HBase, no SPOF

8. Setup and Configuration

9. Setup and Configuration
Job/Task Trackers

10. Setup and Configuration
Job/Task Trackers
On already established cluster

11. Setup and Configuration
Job/Task Trackers
On already established cluster
Overlays Cassandra cluster

12. Setup and Configuration
Job/Task Trackers
On already established cluster
Overlays Cassandra cluster
Hybrid

13. Setup and Configuration
Job/Task Trackers
On already established cluster
Overlays Cassandra cluster
Hybrid
Locality

14. Setup and Configuration
Job/Task Trackers
On already established cluster
Overlays Cassandra cluster
Hybrid
Locality
Gives data’s host information to job tracker

15. Setup and Configuration
Job/Task Trackers
On already established cluster
Overlays Cassandra cluster
Hybrid
Locality
Gives data’s host information to job tracker
Configure both topologies - Cassandra + Hadoop

16. A Separate Cluster

17. A Complete Overlay
Separate
Job Tracker
Task Trackers
Collocated with
Cassandra Nodes

18. A Complete Overlay
Separate
Job Tracker
Task Trackers
Collocated with
Cassandra Nodes
- Bonus -
Data locality!

19. A Hybrid Cluster
Task Trackers
on
Cassandra nodes

20. A Hybrid Cluster
- Bonus -
Data locality
Integrate w/Cluster
Task Trackers
on
Cassandra nodes

21. Tutorial
contrib/word_count example

22. Pig + Cassandra
contrib/pig - a Cassandra specific storage backing
Requires latest Pig - 0.7

23. Future Work

24. Future Work
Simple output to Cassandra - Cassandra-1101
OutputFormat, OutputReducer, OutputWriter

25. Future Work
Simple output to Cassandra - Cassandra-1101
OutputFormat, OutputReducer, OutputWriter
Hive support - Cassandra-913

26. Future Work
Simple output to Cassandra - Cassandra-1101
OutputFormat, OutputReducer, OutputWriter
Hive support - Cassandra-913
Optimizations for start/end row - Cassandra-1125

27. Future Work
Simple output to Cassandra - Cassandra-1101
OutputFormat, OutputReducer, OutputWriter
Hive support - Cassandra-913
Optimizations for start/end row - Cassandra-1125
Other refinements based on feedback

28. Questions...
jeromatron on twitter
jeromatron on #cassandra channel on freenode irc
jeremy (dot) hanna (at) rackspace (dot) com