[HDFS-11711] DN should not delete the block On "Too many open files" Exception

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 2.9.0, 3.0.0-alpha4, 2.8.2
• Component/s: datanode
• Target Version/s: 2.8.1
• Hadoop Flags: Reviewed
• Assignee: Brahma Reddy Battula
• Reporter: Brahma Reddy Battula
• Created: 27/Apr/17 14:04
• Updated: 21/May/18 02:42
• Resolved: 07/Jun/17 09:13

Description

Seen the following scenario in one of our customer environment

• while jobclient writing "job.xml" there are pipeline failures and written to only one DN.
• when mapper reading the "job.xml", DN got "Too many open files" (as system exceed limit) and block got deleted. Hence mapper failed to read and job got failed.

Issue Links

• is broken by: HDFS-8492 DN should notify NN when client requests a missing block
• relates to: HDFS-13511 Provide specialized exception when block length cannot be obtained