[TEZ-3958] Add internal vertex priority information into the tez dag.dot debug information

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.10.0
• Assignee: Jaume M
• Reporter: Gopal Vijayaraghavan
• Created: 21/Jun/18 19:50
• Updated: 08/Feb/21 11:52
• Resolved: 28/Aug/18 03:38

Description

Adding the actual vertex priority as computed by Tez into the debug dag.dot file would allows the debugging of task pre-emption issues when the DAG is no longer a tree.

There are pre-emption issues with isomerization of Tez DAGs, where the a R-isomer dag with mirror rotation runs at a different speed than the L-isomer dag, due to priorities at the same level changing due to the vertex-id order.

Since the problem is hard to debug through, it would be good to record the computed priority in the DAG .dot file in the logging directories.

Issue Links

• causes: TEZ-4281 dag_*_priority.dot files should go into a valid log directory
• links to: GitHub Pull Request #23