[HDFS-11164] Mover should avoid unnecessary retries if the block is pinned

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha2
• Component/s: balancer & mover
• Target Version/s: 3.0.0-alpha2
• Hadoop Flags: Reviewed
• Assignee: Rakesh Radhakrishnan
• Reporter: Rakesh Radhakrishnan
• Created: 22/Nov/16 05:58
• Updated: 05/Oct/17 19:12
• Resolved: 14/Dec/16 01:17

Description

When mover is trying to move a pinned block to another datanode, it will internally hits the following IOException and mark the block movement as failure. Since the Mover has dfs.mover.retry.max.attempts configs, it will continue moving this block until it reaches retryMaxAttempts. If the block movement failure(s) are only due to block pinning, then retry is unnecessary. The idea of this jira is to avoid retry attempts of pinned blocks as they won't be able to move to a different node.

2016-11-22 10:56:10,537 WARN org.apache.hadoop.hdfs.server.balancer.Dispatcher: Failed to move blk_1073741825_1001 with size=52 from 127.0.0.1:19501:DISK to 127.0.0.1:19758:ARCHIVE through 127.0.0.1:19501
java.io.IOException: Got error, status=ERROR, status message opReplaceBlock BP-1772076264-10.252.146.200-1479792322960:blk_1073741825_1001 received exception java.io.IOException: Got error, status=ERROR, status message Not able to copy block 1073741825 to /127.0.0.1:19826 because it's pinned , copy block BP-1772076264-10.252.146.200-1479792322960:blk_1073741825_1001 from /127.0.0.1:19501, reportedBlock move is failed
	at org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtoUtil.checkBlockOpStatus(DataTransferProtoUtil.java:118)
	at org.apache.hadoop.hdfs.server.balancer.Dispatcher$PendingMove.receiveResponse(Dispatcher.java:417)
	at org.apache.hadoop.hdfs.server.balancer.Dispatcher$PendingMove.dispatch(Dispatcher.java:358)
	at org.apache.hadoop.hdfs.server.balancer.Dispatcher$PendingMove.access$5(Dispatcher.java:322)
	at org.apache.hadoop.hdfs.server.balancer.Dispatcher$1.run(Dispatcher.java:1075)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)

Issue Links

• is required by: HDFS-11032 [SPS]: Handling of block movement failure at the coordinator datanode
• relates to: HDFS-12599 Remove Mockito dependency from DataNodeTestUtils