20b684f04f
* and addition of TimestampOffset * ApiMayChange * small mention in docs eventsBySlices is intended to be a better way to retrieve all events for an entity type than eventsByTag. The usage of `eventsByTag` for Projections has the major drawback that the number of tags must be decided up-front and can't easily be changed afterwards. Starting with too many tags means much overhead since many projection instances would be running on each node in a small Akka Cluster. Each projection instance polling the database periodically. Starting with too few tags means that it can't be scaled later to more Akka nodes. Instead of tags we can store a slice number by hashing the persistence id. Like `math.abs(persistenceId.hashCode % numberOfSlices)`. Then the Projection query can be a range query of the slices. For example if using 128 slices and running 4 Projection instances the slice ranges would be 0-31, 32-63, 64-95, 96-128. That can easily be split to more Projection instances when needed and still reuse the offsets for the previous range distributions. |
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| akka-persistence-shared/src/test/scala/akka/persistence | ||
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| CODE_OF_CONDUCT.md | ||
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| LICENSE | ||
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Akka 
We believe that writing correct concurrent & distributed, resilient and elastic applications is too hard. Most of the time it's because we are using the wrong tools and the wrong level of abstraction.
Akka is here to change that.
Using the Actor Model we raise the abstraction level and provide a better platform to build correct concurrent and scalable applications. This model is a perfect match for the principles laid out in the Reactive Manifesto.
For resilience, we adopt the "Let it crash" model which the telecom industry has used with great success to build applications that self-heal and systems that never stop.
Actors also provide the abstraction for transparent distribution and the basis for truly scalable and fault-tolerant applications.
Learn more at akka.io.
Reference Documentation
The reference documentation is available at doc.akka.io, for Scala and Java.
Community
You can join these groups and chats to discuss and ask Akka related questions:
- Forums: discuss.akka.io
- Chat room about using Akka:
- Issue tracker:
In addition to that, you may enjoy following:
- The news section of the page, which is updated whenever a new version is released
- The Akka Team Blog
- @akkateam on Twitter
- Questions tagged #akka on StackOverflow
- Projects built with Akka:
Contributing
Contributions are very welcome!
If you see an issue that you'd like to see fixed, the best way to make it happen is to help out by submitting a pull request implementing it.
Refer to the CONTRIBUTING.md file for more details about the workflow, and general hints on how to prepare your pull request. You can also ask for clarifications or guidance in GitHub issues directly, or in the akka/dev chat if a more real time communication would be of benefit.
A chat room is available for all questions related to developing and contributing to Akka:
License
Akka is Open Source and available under the Apache 2 License.