Answer: DBU Cost

The stage’s details page in Spark UI provides summary metrics for completed tasks, including: - **Duration** of tasks. - **GC time**: Total JVM garbage collection time. - **Shuffle spill (memory)**: Size of the deserialized form of the shuffled data in memory. - **Shuffle spill (disk)**: Size of the serialized form of the data on disk. **DBU Cost** is not part of Spark UI metrics. DBU, or Databricks Unit, is a measure of processing capability per hour used for pricing purposes, depending on your cluster configuration. References: - [Spark UI Documentation](https://spark.apache.org/docs/latest/web-ui.html) - [Databricks Pricing](https://www.databricks.com/product/pricing)

Author: LeetQuiz Editorial Team