Cassandra/TimeWindowCompactionStrategy

TimeWindowCompactionStrategy is an alternative to DateTieredCompactionStrategy, developed by Jeff Jirsa. It ships with Cassandra 3.0.7 and later, (where DateTieredCompactionStrategy has been officially deprecated). For Cassandra versions < 3.0.7, it is possible to install time-window compaction out-of-tree.

Source

Wikimedia maintains a Github branch of the repository, with the Maven pom.xml patched to deploy the jar to archiva.wikimedia.org.

Deployment

The compaction strategy is deployed from https://gerrit.wikimedia.org/r/#/admin/projects/operations/software/cassandra-twcs via Scap.

Updating the deploy repo

The deploy repository makes use of git-fat to sync the jar file to a working copy from Archiva, as necessary. If you need to deploy a new version of the strategy, the basic steps are:

1. Build, and deploy to Archiva with Maven.

   $ cat ~/.m2/settings.xml
   <settings>
     <servers>
       <server>
         <id>wikimedia.releases</id>
         <username>archiva-deploy</username>
         <password>PASSWORD_GOES_HERE</password>
       </server>
       <server>
         <id>wikimedia.snapshots</id>
         <username>archiva-deploy</username>
         <password>PASSWORD_GOES_HERE</password>
       </server>
     </servers>
   </settings>
   $ mvn deploy
   ...
   

2. Update the operations/software/cassandra-twcs with the jar

   $ cp /path/to/twcs/target/TimeWindowCompactionStrategy.jar lib/cassandra-v2.2
   $ git add lib/cassandra-v2.2/TimeWindowCompactionStrategy.jar
   $ git commit -m 'Adding TimeWindowCompactionStrategy.jar via git-fat'
   

   Note: Make sure that the jar you add to git is the same one uploaded in #1 (checksums should be matching). See Adding an artifact to your project for additional information.

3. Deploy to the Cassandra nodes (see https://doc.wikimedia.org/mw-tools-scap/)
4. Update the Cassandra classpath entries as necessary (cassandra::extra_classpath in Puppet hiera)