[HDFS-13929] DFSClient leaks data streamer sockets

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.8.0
• Assignee: Unassigned
• Reporter: Daryn Sharp
• Created: 20/Sep/18 15:35
• Updated: 20/Sep/18 15:37

Description

Sockets to DNs may linger in the CLOSE_WAIT state which means the remote peer (DN) closed the socket but the local client has not. The socket does not transition to TIME_WAIT until the java process exits which is indicative of a leaked file descriptor. Interestingly there is always 1 byte remaining to be read.

$ netstat -tnn|fgrep :1004|fgrep -v EST
tcp        1      0 THISHOST:57158         RANDOMHOST:1004         CLOSE_WAIT  
tcp        1      0 THISHOST:40346         RANDOMHOST:1004         CLOSE_WAIT  
tcp        1      0 THISHOST:45504         RANDOMHOST:1004         CLOSE_WAIT  
tcp        1      0 THISHOST:58958         RANDOMHOST:1004         CLOSE_WAIT  
tcp        1      0 THISHOST:45570         RANDOMHOST:1004         CLOSE_WAIT  
tcp        1      0 THISHOST:46496         RANDOMHOST:1004         CLOSE_WAIT  
tcp        1      0 THISHOST:58944         RANDOMHOST:1004         CLOSE_WAIT  
tcp        1      0 THISHOST:55540         RANDOMHOST:1004         CLOSE_WAIT