「Scala将軍達の後の祭り2017」での発表スライドです。 https://scala-syogun-matsuri.connpass.com/event/53999/

1. Akka Persistence Journal
Ikuo Matsumura
CyberAgent, Inc.
2017-05-14, Scala

2. Akka Persistence
Actor
•
• Actor -> supervisor strategy
• JVM
• JVM
•
2017-05-14, Scala 2

3. Akka Persistence Journal
• Event Sourcing API
• Ka4a, Cassandra, DynamoDB, Redis plugin
• Actor
• Snapshot
2017-05-14, Scala 3

4. "it stores a complete history
of the events associated with
the aggregates in your
domain"
— Reference 3: Introducing Event Sourcing, CQRS
Journey1
1
Dominic Be+s, Julian Dominguez, Grigori Melnik, Fernando Simonazzi, Mani Subramanian,
Exploring CQRS and Event Sourcing, 2012, h+ps://msdn.microsoC.com/en-us/library/
jj554200.aspx
2017-05-14, Scala

5. ( )
• /JVM
•
•
• " " Actor
• , Cameo Pa3ern
2017-05-14, Scala 5

6. : 1 1Actor,
2017-05-14, Scala 6

7. Snapshot
2017-05-14, Scala 7

8. 1. (expire)
• Ka.a, Kinesis, Cassandra, DynamoDB, Redis etc.
2. LRU (evict)
• Redis etc.
2017-05-14, Scala 8

9. 2017-05-14, Scala 9

10. 1 - remember-en))es
akka.cluster.sharding {
remember-entities = on
}
JVM
!
! actor ID
→ (?)
2017-05-14, Scala 10

11. 2 - Persistence Query
val src: Source[String, NotUsed] = // persistenceId
PersistenceQuery(system)
.readJournalFor[ScalaReadJournal](
"akka-persistence-redis.read-journal") // Redis
.currentPersistenceIds
src.mapAsyncUnordered(...)( // Akka Stream
persistenceId => (persistenceId))
.runWith(Sink.ignore)
!
"
2017-05-14, Scala 11

12. : Persistence Query
Redis Journal ,
(JVM) 32GB RAM / 8core
• 15 , Actor
• Cat - Sharding Actor Meow ,
3meout=2
• Sweeper - ID 2
, Cluster Singleton
• : Meow
2
snapshot Redis Journal delete
2017-05-14, Scala 12

13. : Actor 400 9GB (→ 1000 20GB)
2017-05-14, Scala 13

14. : Actor 90 10 (→ 1000 2 )
2017-05-14, Scala 14

15. • Akka Persistence Journal
•
• rememberEn55es, Persistence Query
• Redis Persistence Query
• Actor 1000 ,
• : h?ps://github.com/ikuo/cat-cluster
2017-05-14, Scala 15