[HIVE-12043] UGI instances being used in IO elevator threads are incorrect

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: llap
• Assignee: Siddharth Seth
• Reporter: Siddharth Seth
• Created: 06/Oct/15 07:43
• Updated: 17/Feb/16 01:32
• Resolved: 07/Oct/15 01:20

Description

... which leads to FileSystem closed exceptions.

I'm not sure yet if this is a result of the threadpool being used, and UGI not working well with threadpools, or something else.
The UGI instance which was setup - at what looks to be thread creation time - ends up being used for several different reads, ignoring the actual UGI passed in. At some point this changes to a new incorrect UGI.

A simple fix is to propagate the correct UGI all the way to the reader, and that fixes the FileSystem Closed exception. Figuring out the precise reason would be good though.

Related to HIVE-9898.