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Takanobu Asanuma commented on HDFS-11179: ----------------------------------------- Thanks for the comments, [~jojochuang], [~djp]. That's right, I have just observed {{postponedMisreplicatedBlocksCount}} has been going below zero at the moment. I'd like to set lower priority. > LightWeightHashSet can't remove blocks correctly which have a large number > blockId > ---------------------------------------------------------------------------------- > > Key: HDFS-11179 > URL: https://issues.apache.org/jira/browse/HDFS-11179 > Project: Hadoop HDFS > Issue Type: Bug > Components: namenode > Affects Versions: 3.0.0-alpha1 > Reporter: Takanobu Asanuma > Assignee: Takanobu Asanuma > Priority: Blocker > > Our test cluster has faced a problem that > {{postponedMisreplicatedBlocksCount}} has been going below zero. The version > of the cluster is a recent 3.0. We haven't created any EC files yet. This is > the NN's log: > {noformat} > Rescan of postponedMisreplicatedBlocks completed in 13 msecs. 448 blocks are > left. 176 blocks are removed. > Rescan of postponedMisreplicatedBlocks completed in 13 msecs. 272 blocks are > left. 176 blocks are removed. > Rescan of postponedMisreplicatedBlocks completed in 14 msecs. 96 blocks are > left. 176 blocks are removed. > Rescan of postponedMisreplicatedBlocks completed in 327 msecs. -77 blocks are > left. 177 blocks are removed. > Rescan of postponedMisreplicatedBlocks completed in 15 msecs. -253 blocks are > left. 179 blocks are removed. > Rescan of postponedMisreplicatedBlocks completed in 14 msecs. -432 blocks are > left. 179 blocks are removed. > {noformat} > I looked into this issue and found that it is caused by > {{LightWeightHashSet}} which is used for {{postponedMisreplicatedBlocks}} > recently. When {{LightWeightHashSet}} remove blocks which have a large number > blockId, overflows happen and the blocks can't be removed correctly(, let > alone ec blocks whose blockId starts with the minimum of long). -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org