hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Masatake Iwasaki (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (HDFS-1172) Blocks in newly completed files are considered under-replicated too quickly
Date Tue, 29 Sep 2015 03:47:04 GMT

     [ https://issues.apache.org/jira/browse/HDFS-1172?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Masatake Iwasaki updated HDFS-1172:
-----------------------------------
    Attachment: HDFS-1172.010.patch

bq. Also if a block's effective replica number (including pending replica number) is >=
than its replication factor, the block should not be in neededReplication. 

I rethinked about this and fixed {{checkReplication}} accordingly.

I also fixed to address checkstyle warnings. Warning about file length of BlockManager.java
is not introduced here. The failure of {{TestBlockManager.testBlocksAreNotUnderreplicatedInSingleRack}}
seems not to be related to the patch and I could not reproduce it in my environment.


> Blocks in newly completed files are considered under-replicated too quickly
> ---------------------------------------------------------------------------
>
>                 Key: HDFS-1172
>                 URL: https://issues.apache.org/jira/browse/HDFS-1172
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: namenode
>    Affects Versions: 0.21.0
>            Reporter: Todd Lipcon
>         Attachments: HDFS-1172-150907.patch, HDFS-1172.008.patch, HDFS-1172.009.patch,
HDFS-1172.010.patch, HDFS-1172.patch, hdfs-1172.txt, hdfs-1172.txt, replicateBlocksFUC.patch,
replicateBlocksFUC1.patch, replicateBlocksFUC1.patch
>
>
> I've seen this for a long time, and imagine it's a known issue, but couldn't find an
existing JIRA. It often happens that we see the NN schedule replication on the last block
of files very quickly after they're completed, before the other DNs in the pipeline have a
chance to report the new block. This results in a lot of extra replication work on the cluster,
as we replicate the block and then end up with multiple excess replicas which are very quickly
deleted.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message