Jepsen Introduction LT

Jepsenの紹介LT

Transcript

1. 2015/5/13 Dwango Internal Erlang/OTP study group, LT
   Kota UENISHI / @kuenishi
   JEPSEN “CALL ME MAYBE”
   

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2. “Call Me Maybe”
   WHAT EVEN IS JEPSEN?
   

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3. Who plays a song “Call Me Maybe”
   A NAME OF A SINGER
   

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4. That can test many system with replication
   ALSO,
   A PARTITION TOLERANCE
   TEST TOOL
   

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5. IT HAS TESTED …
   • PostgreSQL
   • Redis (Sentinel, redux)
   • MongoDB
   • Riak
   • ZooKeeper
   • NuoDB
   • Kafka
   • Cassandra
   • RabbitMQ
   • etcd and Consul
   • Elasticsearch
   • Aerospike (New!)
   

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6. AND FOUND DATA LOSS
   ISSUE OF …
   • Redis (Sentinel, redux)
   • MongoDB
   • Kafka
   • Cassandra
   • RabbitMQ
   • etcd
   • Elasticsearch
   • Aerospike
   

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7. BOXES AND LINES
   n1
   jepsen
   n2 n3
   n4 n5
   

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8. is implemented in Clojure
   TECHNICALLY JEPSEN ..
   • Emulates network partition
   • By cutting network between virtual machines
   • While Jepsen concurrently continues writing data,
   • And finally verifies any writes are not lost
   

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9. WHY PARTITION TOLERANCE
   IS IMPORTANT AND
   DIFFICULT?
   

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10. • In the beginning was the failure and asynchrony
    • Replication and Consensus next
    • Failover and recovery / Membership Change
    mess things
    • Implementation and runtime is complexed
    

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11. • for x=1….n
    • list = get(x)
    • write(x, [a, list])
    • get(x)
    • => [1…n] ͱͳ͍ͬͯΕ͹ linearizable
    

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12. REFERENCES
    • C.R.Jepsen “Call Me Maybe”
    • Jepsen blog post series
    • github.com/aphyr/jepsen
    • Kyle Kingsbury: @aphyr (sometimes NSFW)
    • “The Network Is Reliable”
    • https://queue.acm.org/detail.cfm?id=2655736
    

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