[IMPALA-4654] Kudu scanner threads take a long time to close

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: Impala 2.8.0
• Fix Version/s: Impala 2.8.0
• Component/s: Backend
• Labels: kudu memory query-lifecycle resource-management
• Target Version: Impala 2.8.0
• Assignee: Matthew Jacobs
• Reporter: Matthew Jacobs
• Created: 12/Dec/16 22:06
• Updated: 24/Jan/17 04:16
• Resolved: 15/Dec/16 01:37

Description

After a recent Kudu change (somewhere between a70c90 and e018a83), we started noticing that Kudu scanner threads were taking longer to Close(). This led to some test failures (see IMPALA-4642 and IMPALA-4645), which are going to be addressed by waiting longer for fragments to complete.

However, we need to understand why the scanner threads are taking so long.