The BookKeeper journal manager is an implementation of the HDFS JournalManager interface. The JournalManager interface allows you to plug custom write ahead logging into the HDFS NameNode.

Setting up the BookKeeper Journal Manager

http://zookeeper.apache.org/bookkeeper/docs/r4.0.0/bookkeeperConfig.html^{Image Removed} covers the step necessary to set up a BookKeeper cluster. We recommend that you use at least 3 servers to ensure fault tolerance.

Once BookKeeper has been set up, you can configure the journal manager. Currently, JournalManagers are only available in trunk and 0.23.3 branches. BookKeeper JournalManager is available in trunk, but the most recent version is at https://github.com/ivankelly/hadoop-common/tree/BKJM-benching^{Image Removed}. All the changes in this branch are pending submission into trunk. For this guide we will use this branch.

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This will configure the namenode with 1 local edits dir and 1 bookkeeper edits dir. The BookKeeperJournalManager connects to localhost:2181 as the ZooKeeper server. Note that this will not start the namenode is in high availability mode, but BookKeeperJournalManager can similarly be used as a shared edits dir in HA.

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The web interface should now be available at http://localhost:50070/^{Image Removed}.

Benchmarks

We ran benchmarks on a cluster of machines with:

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