Shinichi Yamashita created HDFS-6833: ----------------------------------------
Summary: DirectoryScanner should not register a deleting block with memory of DataNode Key: HDFS-6833 URL: https://issues.apache.org/jira/browse/HDFS-6833 Project: Hadoop HDFS Issue Type: Bug Components: datanode Affects Versions: 3.0.0 Reporter: Shinichi Yamashita Assignee: Shinichi Yamashita When a block is deleted in DataNode, the following messages are usually output. {code} 2014-08-07 17:53:11,606 INFO org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetAsyncDiskService: Scheduling blk_1073741825_1001 file /hadoop/data1/dfs/data/current/BP-1887080305-172.28.0.101-1407398838872/current/finalized/subdir0/subdir0/blk_1073741825 for deletion 2014-08-07 17:53:11,617 INFO org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetAsyncDiskService: Deleted BP-1887080305-172.28.0.101-1407398838872 blk_1073741825_1001 file /hadoop/data1/dfs/data/current/BP-1887080305-172.28.0.101-1407398838872/current/finalized/subdir0/subdir0/blk_1073741825 {code} However, DirectoryScanner may be executed when DataNode deletes the block in the current implementation. And the following messsages are output. {code} 2014-08-07 17:53:30,519 INFO org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetAsyncDiskService: Scheduling blk_1073741825_1001 file /hadoop/data1/dfs/data/current/BP-1887080305-172.28.0.101-1407398838872/current/finalized/subdir0/subdir0/blk_1073741825 for deletion 2014-08-07 17:53:31,426 INFO org.apache.hadoop.hdfs.server.datanode.DirectoryScanner: BlockPool BP-1887080305-172.28.0.101-1407398838872 Total blocks: 1, missing metadata files:0, missing block files:0, missing blocks in memory:1, mismatched blocks:0 2014-08-07 17:53:31,426 WARN org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetImpl: Added missing block to memory FinalizedReplica, blk_1073741825_1001, FINALIZED getNumBytes() = 21230663 getBytesOnDisk() = 21230663 getVisibleLength()= 21230663 getVolume() = /hadoop/data1/dfs/data/current getBlockFile() = /hadoop/data1/dfs/data/current/BP-1887080305-172.28.0.101-1407398838872/current/finalized/subdir0/subdir0/blk_1073741825 unlinked =false 2014-08-07 17:53:31,531 INFO org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetAsyncDiskService: Deleted BP-1887080305-172.28.0.101-1407398838872 blk_1073741825_1001 file /hadoop/data1/dfs/data/current/BP-1887080305-172.28.0.101-1407398838872/current/finalized/subdir0/subdir0/blk_1073741825 {code} Deleting block information is registered in DataNode's memory. And when DataNode sends a block report, NameNode receives wrong block information. For example, when we execute recommission or change the number of replication, NameNode may delete the right block as "ExcessReplicate" by this problem. And "Under-Replicated Blocks" and "Missing Blocks" occur. When DataNode run DirectoryScanner, DataNode should not register a deleting block. -- This message was sent by Atlassian JIRA (v6.2#6252)