Chronicle Map
SmoothieMap
Chronicle Map | SmoothieMap | |
---|---|---|
4 | 1 | |
2,687 | 292 | |
0.5% | 1.0% | |
8.4 | 0.0 | |
5 days ago | over 4 years ago | |
Java | Java | |
Apache License 2.0 | - |
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Chronicle Map
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GC, hands off my data!
I decided to start with an overview of what open-source options are currently available. When it comes to the implementation of the on-heap cache mechanism, the options are numerous – there is well known: guava, ehcache, caffeine and many other solutions. However, when I began researching cache mechanisms offering the possibility of storing data outside GC control, I found out that there are very few solutions left. Out of the popular ones, only Terracotta is supported. It seems that this is a very niche solution and we do not have many options to choose from. In terms of less-known projects, I came across Chronicle-Map, MapDB and OHC. I chose the last one because it was created as part of the Cassandra project, which I had some experience with and was curious about how this component worked:
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Off-heap memory in Java
Chronicle-Map: Chronicle Map is an in-memory, key-value store, designed for low-latency, and/or multi-process applications.
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Solution for hash-map with >100M values
I've wrangled data sets in the ~600gb range using nothing but plain old Java and a few beefy boxes. This can all be kept in memory, but you have to go off-heap. You can use Chronicle Map and Chronicle Values to model this data and work with it off-heap in a way that's still very clean and object oriented. 128gb of RAM is cheap these days, whether you're in the cloud or not.
SmoothieMap
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Solution for hash-map with >100M values
Try https://github.com/TimeAndSpaceIO/SmoothieMap
What are some alternatives?
MapDB - MapDB provides concurrent Maps, Sets and Queues backed by disk storage or off-heap-memory. It is a fast and easy to use embedded Java database engine.
java-concurrent-hash-trie-map - Java port of a concurrent trie hash map implementation from the Scala collections library
Redisson - Redisson - Easy Redis Java client and Real-Time Data Platform. Sync/Async/RxJava/Reactive API. Over 50 Redis based Java objects and services: Set, Multimap, SortedSet, Map, List, Queue, Deque, Semaphore, Lock, AtomicLong, Map Reduce, Bloom filter, Spring Cache, Tomcat, Scheduler, JCache API, Hibernate, RPC, local cache ...
JetBrains Xodus - Transactional schema-less embedded database used by JetBrains YouTrack and JetBrains Hub.
lasher - Lasher is an embeddable key-value store written in Java.
H2 - H2 is an embeddable RDBMS written in Java.
Oak - A Scalable Concurrent Key-Value Map for Big Data Analytics
Jedis - Redis Java client
Speedment - Speedment is a Stream ORM Java Toolkit and Runtime
HikariCP - 光 HikariCP・A solid, high-performance, JDBC connection pool at last.
Realm - Realm is a mobile database: a replacement for SQLite & ORMs