[
https://issues.apache.org/jira/browse/HDFS-6833?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Shinichi Yamashita updated HDFS-6833:
-------------------------------------
Attachment: HDFS-6833-6-3.patch
Hi [~yzhangal],
Thank you for your further comments. And I'm sorry for the late reply.
I attatch the renew patch file.
bq. ConcurrentModificationException
When I tested the patch of the previous version, I confirmed that the following
messages were output. And I changed to iterator-while-remove code.
{code}
2014-08-11 21:28:01,795 ERROR
org.apache.hadoop.hdfs.server.datanode.DirectoryScanner: Exception during
DirectoryScanner execution - will continue next cycle
java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextEntry(HashMap.java:922)
at java.util.HashMap$ValueIterator.next(HashMap.java:950)
at
org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetImpl.removeDeletedBlocks(FsDatasetImpl.java:1968)
at
org.apache.hadoop.hdfs.server.datanode.DirectoryScanner.scan(DirectoryScanner.java:498)
at
org.apache.hadoop.hdfs.server.datanode.DirectoryScanner.reconcile(DirectoryScanner.java:404)
at
org.apache.hadoop.hdfs.server.datanode.DirectoryScanner.run(DirectoryScanner.java:360)
at
java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:304)
at
java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:178)
at
java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
{code}
> 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, 2.5.0
> Reporter: Shinichi Yamashita
> Assignee: Shinichi Yamashita
> Attachments: HDFS-6833-6-2.patch, HDFS-6833-6-3.patch,
> HDFS-6833-6.patch, HDFS-6833-7-2.patch, HDFS-6833-7.patch, HDFS-6833.patch,
> HDFS-6833.patch, HDFS-6833.patch, HDFS-6833.patch, HDFS-6833.patch
>
>
> 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)
