Cassandra Reading 02-01-2012
Recent Cassandra reading.
CQL: SQL In Cassandra
And a blog post
By Eric Evans
- Good examples of simple statements.
- Performance comparisons show CQL has 5% to 10% lower throughput and higher latency.
- List of drivers and where to get them.
- More improvements coming.
Storm Cassandra Integration
By P. Taylor Goetz
- A storm bolt to persist data to Cassandra.
Cassandra in Online Advertising: Real Time Bidding
By Edward Capriolo
- 10TB of data and growing.
- Latency requirements of less than 120ms.
- “Distributed not Duplicated” is a great phrase.
- Ed still loves the Cacti :)
- Good idea to use JMX to modify the (Cassandra) cache settings for a single node to compare against the others.
- Pay attention to how the cache hit rate varies with regard to the cache size, at some point may be better to accept a (say) 90% hit rate and give more memory to another CF.
- Tuning IO performance for peak and off-peak by modifying
nodetool setcompactionlimitto improve compaction performance.
- Running night time major compactions like Urban Airship. I wonder how leveled compaction would work with the mixed workload?
Replication and the latency-consistency tradeoff
By Daniel Abadi
- A discussion about latency and consistency.
- “there’s no way to perform consistent replication across database replicas without some level of synchronous network communication.”
- Not sure I agree that in Dynamo / Cassandra (not sure about Riak) “updates generally go to the same node, and are then propagated synchronously to W other nodes (case (2)(c))”.
- I think how inconsistencies are handled during read requests is another source of latency.
Cassandra for sys admins
By Nathan Milford
- 14 nodes in two DC’s
- In productions since Cassandra version 0.4, awesome!
- A good list of things to monitor in a cluster.
- Good best practices for shutting down a node that give the fastest startup, also see.
Cassandra for LOBS
By Dan Pritchett
- Expensive SAN storage bombshell.
Expedia Hotel Price Cache
By B. Todd Burruss
- Pre-calculate, trading space for time.
- A rolling window of 2.8 billion data points.
- Test, measure, tune.
Data Modeling Examples
By Matthew Dennis
- I always check out Matthew’s data model presentations to see what the best practices are.
- “Usually better to keep a record that something happened as opposed to changing a value”.
- Good advice on time series and the XACT_LOG.
Cassandra In Production: Things We Learned
By Walt Jones
- Using Cassandra 0.7, there are a lot of improvements in Cassandra 1.0.
- 12 AWS EC2 m1.xlarge nodes with 5TB of data.
- S3 archive
- The memory footprint issues has been eliminated in Cassandra 1.0.
- Please avoid using Super Columns.
- Please use the Random Partitioner.
Data Modeling with Cassandra
By Sam Overton
- De-normalize for a brighter future.
- No SQL “Hello World” twitter example.