Using Counters to Identify the Cause of Slow-Performing Jobs
Tez View shows counters so you can understand why a task performs more slowly than expected. Counters help you better understand the task size and enable you to locate anomalies. Elapsed time is one of the primary counters to look for.
Counters are available at the DAG, vertex, and task levels. As of Tez View in Ambari 2.5.0, the following Hive LLAP counter information is displayed:
Group:
org.apache.hadoop.hive.llap.counters.LlapIOCounters |
Counters: CACHE_HIT_BYTES, CACHE_MISS_BYTES, METADATA_CACHE_HIT,
METADATA_CACHE_MISS |
As of Tez View in Ambari 2.5.0, the Vertex Swimlane tab is also available. The information here is about vertex processor details for Hive and Pig.
If you want to view the information about the vertex processing in a different format, open a vertex to see the Vertex Details sutab. A Description pane at the bottom of the window is from the user payload of the respective vertex in the DAG plan.
Monitoring Task Progress for Jobs
The Tez View shows task progress by increasing the count of completed tasks and total tasks. This enables you to identify the tasks that might be "hung" and to understand more about long-running tasks.