Tuning Guide
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Performance Monitoring

Prior to switching over to the new Storm Kafka client, which leverages the new Kafka consumer API, HCP stored offsets in ZooKeeper. While the broker hosts are still stored in ZooKeeper, offsets are now stored in Kafka. This is a configurable option, and you may switch back to ZooKeeper if you choose. However, Metron currently uses the new defaults. And there are some useful tools that come with Storm and Kafka that we can use to monitor our topologies.