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https://issues.apache.org/jira/browse/HDFS-17179?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17762377#comment-17762377
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Bryan Beaudreault commented on HDFS-17179:
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Digging further into this, I’m realizing that DFSInputStream cannot handle this
exception. It’s caught way before reaching there, and the stacktrace I shared
is printed as part of a WARN. The BlockReaderLocal will fail to build, and we
will fallback to BlockReaderRemote, which will contact the DataNode with
Op.READ_BLOCK. The DataNode will handle this exception if checksums are
enabled. If checksums are not enabled, it won’t even try to load the
MetaHeader.
I think the bug here, if any, is that BlockReaderLocal should work similar to
DataNode — the MetaHeader is only used for checksums, so only read it if
checksums are enabled. This is easier said than done because of how
BlockReaderLocal uses checksum metadata throughout the code for determining
read sizes, etc even if checksums are disabled. It’s probably doable but will
require some refactoring to do it safely.
> DFSInputStream should report CorruptMetaHeaderException as corruptBlock to
> NameNode
> -----------------------------------------------------------------------------------
>
> Key: HDFS-17179
> URL: https://issues.apache.org/jira/browse/HDFS-17179
> Project: Hadoop HDFS
> Issue Type: Improvement
> Reporter: Bryan Beaudreault
> Assignee: Bryan Beaudreault
> Priority: Major
>
> We've been running into some data corruption issues recently. When a
> ChecksumException is thrown, DFSInputStream correctly reports the block to
> the NameNode which triggers deletion and re-replication of the replica. It's
> also possible that we fail to even read the meta header for constructing the
> checksum. This gets thrown as CorruptMetaHeaderException which is not handled
> by DFSInputStream. We should handle this similarly to ChecksumException. See
> stacktrace:
>
> {code:java}
> WARN org.apache.hadoop.hdfs.client.impl.BlockReaderFactory:
> BlockReaderFactory(fileName=/hbase/data/default/table-c1/5a76502c2c7be37b2d92057baa8a3d81/0/24ddc16e2d824a3bb9bf242ad950a589,
> block=BP-154245500-xxxxxx-1657570070866:blk_1362550389_288818622): error
> creating ShortCircuitReplica.
> org.apache.hadoop.hdfs.server.datanode.CorruptMetaHeaderException: The block
> meta file header is corrupt
> at
> org.apache.hadoop.hdfs.server.datanode.BlockMetadataHeader.preadHeader(BlockMetadataHeader.java:133)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplica.<init>(ShortCircuitReplica.java:129)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.client.impl.BlockReaderFactory.requestFileDescriptors(BlockReaderFactory.java:618)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.client.impl.BlockReaderFactory.createShortCircuitReplicaInfo(BlockReaderFactory.java:545)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.create(ShortCircuitCache.java:786)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.fetchOrCreate(ShortCircuitCache.java:723)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.client.impl.BlockReaderFactory.getBlockReaderLocal(BlockReaderFactory.java:483)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.client.impl.BlockReaderFactory.build(BlockReaderFactory.java:360)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.DFSInputStream.getBlockReader(DFSInputStream.java:715)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.DFSInputStream.actualGetFromOneDataNode(DFSInputStream.java:1160)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.DFSInputStream$2.call(DFSInputStream.java:1132)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.DFSInputStream$2.call(DFSInputStream.java:1128)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> at java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[?:?]
> at
> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) ~[?:?]
> at java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[?:?]
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
> ~[?:?]
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
> ~[?:?]
> at java.lang.Thread.run(Thread.java:829) ~[?:?]
> Caused by: org.apache.hadoop.util.InvalidChecksumSizeException: The value -75
> does not map to a valid checksum Type
> at
> org.apache.hadoop.util.DataChecksum.mapByteToChecksumType(DataChecksum.java:190)
> ~[hadoop-common-3.3.1.jar:?]
> at
> org.apache.hadoop.util.DataChecksum.newDataChecksum(DataChecksum.java:159)
> ~[hadoop-common-3.3.1.jar:?]
> at
> org.apache.hadoop.hdfs.server.datanode.BlockMetadataHeader.preadHeader(BlockMetadataHeader.java:131)
> ~[hadoop-hdfs-client-3.3.1.jar:?]
> WARN org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache:
> ShortCircuitCache(0x4da4703d): failed to load
> 1362550389_BP-154245500-xxxxxxx-1657570070866{code}
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