Issue 205: Avoid copying bytebuf for constructing log record to write

Descriptions of the changes in this PR:

- avoid copying memory for writer facing constructor for log records
- construct a ByteBuf by copying ByteBuffer for reader facing constructors

This closes #205, #206 
tree: 9dea8af001c7e2ab718c866520e6ebd1fd918c6d
  1. .github/
  2. deploy/
  3. distributedlog-benchmark/
  4. distributedlog-build-tools/
  5. distributedlog-common/
  6. distributedlog-core/
  7. distributedlog-core-twitter/
  8. distributedlog-dist/
  9. distributedlog-protocol/
  10. distributedlog-proxy-client/
  11. distributedlog-proxy-protocol/
  12. distributedlog-proxy-server/
  13. distributedlog-tutorials/
  14. docker/
  15. scripts/
  16. src/
  17. tests/
  18. vagrant/
  19. website/
  20. .gitignore
  21. .travis.yml
  22. ChangeLog
  24. NOTICE
  25. pom.xml
  27. Vagrantfile


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Apache DistributedLog

Apache DistributedLog (DL) is a high-throughput, low-latency replicated log service, offering durability, replication and strong consistency as essentials for building reliable real-time applications.


Apache DistributedLog project graduated from Incubator at July 2017. It is now a sub-project of Apache BookKeeper.


High Performance

DL is able to provide milliseconds latency on durable writes with a large number of concurrent logs, and handle high volume reads and writes per second from thousands of clients.

Durable and Consistent

Messages are persisted on disk and replicated to store multiple copies to prevent data loss. They are guaranteed to be consistent among writers and readers in terms of strict ordering.

Efficient Fan-in and Fan-out

DL provides an efficient service layer that is optimized for running in a multi- tenant datacenter environment such as Mesos or Yarn. The service layer is able to support large scale writes (fan-in) and reads (fan-out).

Various Workloads

DL supports various workloads from latency-sensitive online transaction processing (OLTP) applications (e.g. WAL for distributed database and in-memory replicated state machines), real-time stream ingestion and computing, to analytical processing.

Multi Tenant

To support a large number of logs for multi-tenants, DL is designed for I/O isolation in real-world workloads.

Layered Architecture

DL has a modern layered architecture design, which separates the stateless service tier from the stateful storage tier. To support large scale writes (fan- in) and reads (fan-out), DL allows scaling storage independent of scaling CPU and memory.

First Steps

Next Steps

Get In Touch

Report a Bug

For filing bugs, suggesting improvements, or requesting new features, help us out by opening a jira.

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Join us on Slack - This is the most immediate way to connect with DistributedLog committers and contributors.


We feel that a welcoming open community is important and welcome contributions.

Contributing Code

  1. See Developer Guide to get your local environment setup.

  2. Take a look at our open issues.

  3. Review our coding style and follow our code reviews to learn about our conventions.

  4. Make your changes according to our code review workflow.

  5. Checkout the list of project ideas to contribute more features or improvements.

Improving Website and Documentation

  1. See website/ on how to build the website.

  2. See docs/ on how to build the documentation.


Apache DistributedLog is an open source project of The Apache Software Foundation (ASF). The Apache DistributedLog project originated from Twitter.