ApacheCon NA 2010 Session

Cache & Concurrency considerations for a high performance Cassandra deployment.

Cassandra has hit it's stride as a distributed java NoSQL database! It's fast, it's in-memory, it's scalable, it's seda; It's eventually consistent model makes it practical for the large & growing volumes of unstructured data usecases. It is also time to run it through the filters of performance analysis. For starters it runs on the java virtual machine and inherits the capabilities and culpabilities of the platform. This presentation reviews the runtime architecture, cache behavior & performance of a real-world workload on Cassandra. We blend existing system & jvm tools to get a quick overview & a breakdown of hotspots in the get, put & update operations. We highlight the role played by garbage collection & fragmentation due to long lived objects; We investigate lock contention in the data structures under concurrent usage. Cassandra uses UDP for management & TCP for data: we look at robustness of the communication patterns during high spikes and cluster-wide events. We review Non-Blocking Hashmap modifications to Cassandra that improve concurrency & amplify performance of this frontrunner in the NoSQL space