1. Project Voldemort Whenrelationdatabaseis not enough (too much?)

2. Tomasz Nurkiewicz Graduated Warsaw University Of Technology (Faculty of Electronics and Information Technology) SCJP, SCJD, SCWCD, SCBCD Brown belt on JavaBlackBelt.com Fewcommitsin: Commons Lang, Logback, Mule ESB Currentlyworking as a developer atJAVART http://nurkiewicz.blogspot.com

3. WhatisVoldemort not? Relationaldatabase Alternative API to RDB Distributedcache

4. ...so? Key-valuedatabase „PersistentHashMap” Keywords: Clusterready Scalability (no master) Efficient (partitioning) High availability „Less than” relationdatabase

5. Voldemortvs. HashMap Partitionsvs. hash-buckets Whereis my stuff? – clientsiderouting 0 4 8 12 16 node1 1 5 9 13 17 node2 2 6 10 14 18 node3 3 7 11 15 19 node4

6. API – StoreClient<K, V> getValue(K key): V getAll(Iterable<K> keys): Map<K, V> put(K key, V value) delete(K key): boolean getResponsibleNodes(K key): List<Node> … extendsjava.util.Map<K, V>?

7. Voldemortcluster DEMO node1 node2 node3 node4 localhost:6101 localhost:6102 localhost:6103 localhost:6104

8. Connection (One to rulethemall) ClientConfigconfig = newClientConfig(); config.setBootstrapUrls("tcp://server:6101"); SocketStoreClientFactoryfactory = newSocketStoreClientFactory(config); StoreClient<K, V> client = factory.getStoreClient("users"); No replication – efficient, but risky

9. Storeconfiguration (stores.xml) N (<replication-factor>) R (<required-reads>) W (<required-writes>) Serialization JSON – onlyprimitives, dates and collections protobuf – (Google) String (e.g. XML) Java (Serializable)

10. Clusterconfiguration (cluster.xml) <cluster> <name>Usercluster</name> <server> <id>1</id> <host>192.168.0.17</host> <socket-port>6101</socket-port> <partitions>0, 4, 8, 12, 16</partitions> </server> Persistency: MySQL, Berkeley DB, RAM

11. Rebalancing 0 4 8 12 16 node1 1 5 9 13 17 node2 2 6 10 14 18 node3 3 7 11 15 19 node4 node5

14. Whatelse? JMX (bothclient and server) Views (non-materialized) HTTP interface (not REST though) Hintedhandoff

15. Happy clustering! http://project-voldemort.com http://www.infoq.com/presentations/Project-Voldemort-Scaling-Simple-Storage http://www.infoq.com/presentations/Project-Voldemort-at-Gilt-Groupe http://behemoth.strlen.net/~alex/voldemort-nosql_live.ppt http://www.slideshare.net/hadoopusergroup/hadoop-and-voldemort-linkedin http://www.vineetgupta.com/2010/01/nosql-databases-part-1-landscape.html http://www.metabrew.com/article/anti-rdbms-a-list-of-distributed-key-value-stores