Mailing-List: contact hdfs-issues-help@hadoop.apache.org; run by ezmlm
Precedence: bulk
Reply-To: hdfs-issues@hadoop.apache.org
Date: Fri, 1 Feb 2013 12:41:10 +0000 (UTC)
From: "Hudson (JIRA)" <jira@apache.org>
To: hdfs-issues@hadoop.apache.org
Message-ID: <JIRA.12364362.1173290319314.229200.1359722470134@arcas>
In-Reply-To: <JIRA.12364362.1173290319314@arcas>
References: <JIRA.12364362.1173290319314@arcas>
Subject: [jira] [Commented] (HDFS-395) DFS Scalability: Incremental block
 reports
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


    [ https://issues.apache.org/jira/browse/HDFS-395?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13568706#comment-13568706 ] 

Hudson commented on HDFS-395:
-----------------------------

Integrated in Hadoop-Hdfs-0.23-Build #512 (See [https://builds.apache.org/job/Hadoop-Hdfs-0.23-Build/512/])
    merge -r 1161991:1161992 Merging from trunk to branch-0.23 to fix HDFS-395 (Revision 1441117)

     Result = SUCCESS
kihwal : http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1441117
Files : 
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockManager.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BPOfferService.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DNConf.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/FSDataset.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/FSDatasetAsyncDiskService.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/BlockCommand.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/DatanodeProtocol.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/ReceivedDeletedBlockInfo.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/NNThroughputBenchmark.java
* /hadoop/common/branches/branch-0.23/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestDeadDatanode.java

                
> DFS Scalability: Incremental block reports
> ------------------------------------------
>
>                 Key: HDFS-395
>                 URL: https://issues.apache.org/jira/browse/HDFS-395
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>          Components: datanode, namenode
>            Reporter: dhruba borthakur
>            Assignee: Tomasz Nykiel
>             Fix For: 2.0.0-alpha, 0.23.7
>
>         Attachments: blockReportPeriod.patch, explicitAcks.patch-3, explicitAcks.patch-4, explicitAcks.patch-5, explicitAcks.patch-6, explicitDeleteAcks.patch
>
>
> I have a cluster that has 1800 datanodes. Each datanode has around 50000 blocks and sends a block report to the namenode once every hour. This means that the namenode processes a block report once every 2 seconds. Each block report contains all blocks that the datanode currently hosts. This makes the namenode compare a huge number of blocks that practically remains the same between two consecutive reports. This wastes CPU on the namenode.
> The problem becomes worse when the number of datanodes increases.
> One proposal is to make succeeding block reports (after a successful send of a full block report) be incremental. This will make the namenode process only those blocks that were added/deleted in the last period.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira