[HDFS-15589] Huge PostponedMisreplicatedBlocks can't decrease immediately when start namenode after datanode

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: hdfs

Environment

CentOS 7

• Assignee: Unassigned
• Reporter: zhengchenyu
• Created: 21/Sep/20 12:59
• Updated: 22/Sep/20 07:56

Description

In our test cluster, I restart my namenode. Then I found many PostponedMisreplicatedBlocks which doesn't decrease immediately. 

I search the log below like this. 

2020-09-21 17:02:37,029 DEBUG BlockStateChange: *BLOCK* NameNode.blockReport: from DatanodeRegistration(xx.xx.xx.xx:9866, datanodeUuid=c6a9934f-afd4-4437-b976-fed55173ce57, infoPort=9864, infoSecurePort=0, ipcPort=9867, storageInfo=lv=-57;cid=CID-9f6d0a32-e51c-459a-9f65-6e7b5791ee25;nsid=1016509846;c=1592578350834), reports.length=12
2020-09-21 17:02:37,029 DEBUG BlockStateChange: *BLOCK* NameNode.blockReport: from DatanodeRegistration(xx.xx.xx.xx:9866, datanodeUuid=aee144f1-2082-4bca-a92b-f3c154a71c65, infoPort=9864, infoSecurePort=0, ipcPort=9867, storageInfo=lv=-57;cid=CID-9f6d0a32-e51c-459a-9f65-6e7b5791ee25;nsid=1016509846;c=1592578350834), reports.length=12
2020-09-21 17:02:37,029 DEBUG BlockStateChange: *BLOCK* NameNode.blockReport: from DatanodeRegistration(xx.xx.xx.xx:9866, datanodeUuid=d152fa5b-1089-4bfc-b9c4-e3a7d98c7a7b, infoPort=9864, infoSecurePort=0, ipcPort=9867, storageInfo=lv=-57;cid=CID-9f6d0a32-e51c-459a-9f65-6e7b5791ee25;nsid=1016509846;c=1592578350834), reports.length=12
2020-09-21 17:02:37,156 DEBUG BlockStateChange: *BLOCK* NameNode.blockReport: from DatanodeRegistration(xx.xx.xx.xx:9866, datanodeUuid=5cffc1fe-ace9-4af8-adfc-6002a7f5565d, infoPort=9864, infoSecurePort=0, ipcPort=9867, storageInfo=lv=-57;cid=CID-9f6d0a32-e51c-459a-9f65-6e7b5791ee25;nsid=1016509846;c=1592578350834), reports.length=12
2020-09-21 17:02:37,161 DEBUG BlockStateChange: *BLOCK* NameNode.blockReport: from DatanodeRegistration(xx.xx.xx.xx:9866, datanodeUuid=9980d8e1-b0d9-4657-b97d-c803f82c1459, infoPort=9864, infoSecurePort=0, ipcPort=9867, storageInfo=lv=-57;cid=CID-9f6d0a32-e51c-459a-9f65-6e7b5791ee25;nsid=1016509846;c=1592578350834), reports.length=12
2020-09-21 17:02:37,197 DEBUG BlockStateChange: *BLOCK* NameNode.blockReport: from DatanodeRegistration(xx.xx.xx.xx:9866, datanodeUuid=77ff3f5e-37f0-405f-a16c-166311546cae, infoPort=9864, infoSecurePort=0, ipcPort=9867, storageInfo=lv=-57;cid=CID-9f6d0a32-e51c-459a-9f65-6e7b5791ee25;nsid=1016509846;c=1592578350834), reports.length=12

Node: test cluster only have 6 datanode.

You will see the blockreport called before "Marking all datanodes as stale" which is logged by startActiveServices. But DatanodeStorageInfo.blockContentsStale only set to false in blockreport, then startActiveServices set all datnaode to stale node. So the datanodes will keep stale util next blockreport, then PostponedMisreplicatedBlocks keep a huge number.