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https://issues.apache.org/jira/browse/SQOOP-604?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13489952#comment-13489952
 ] 

Hudson commented on SQOOP-604:
------------------------------

Integrated in Sqoop-ant-jdk-1.6-hadoop200 #269 (See 
[https://builds.apache.org/job/Sqoop-ant-jdk-1.6-hadoop200/269/])
    SQOOP-604: Easy throttling feature for MySQL exports (Revision 
c499f49097ebf04f9fac34f1df768a319e679cea)

     Result = SUCCESS
abhijeet : 
https://git-wip-us.apache.org/repos/asf?p=sqoop.git&a=commit&h=c499f49097ebf04f9fac34f1df768a319e679cea
Files : 
* src/java/org/apache/sqoop/mapreduce/MySQLExportMapper.java

                
> Easy throttling feature for MySQL exports
> -----------------------------------------
>
>                 Key: SQOOP-604
>                 URL: https://issues.apache.org/jira/browse/SQOOP-604
>             Project: Sqoop
>          Issue Type: Improvement
>          Components: connectors/mysql
>    Affects Versions: 1.4.2
>            Reporter: Zoltan Toth-Czifra
>            Priority: Minor
>             Fix For: 1.4.3
>
>         Attachments: SQOOP-604_v6.patch
>
>
> Sqoop always tries to achieve the best possible throughput with exports, 
> which might not be desirable in all cases. Sometimes we need to export large 
> data with Sqoop to a live relational database (MySQL in our case), that is, a 
> database that is under a high load serving random queries from the users of 
> our product.
> While data consistency issues during the export can be easily solved with a 
> staging table, there is still a problem: the performance impact caused by the 
> heavy export. 
> First off, the resources of MySQL dedicated to the import process can affect 
> the performance of the live product, both on the master and on the slaves. 
> Second, even if the servers can handle the import with no significant 
> performance impact (mysqlimport should be relatively "cheap"), importing big 
> tables (GB+) can cause serious replication lag in the cluster risking data 
> consistency.
> My suggestion is quite simple. Using the already existing "checkpoint" 
> feature of the MySQL exports (the export process is restarted every X bytes 
> written), extending it with a new config value that would simply make the 
> thread sleep for X milliseconds at the checkbpoints. With low enough byte 
> count limit this can be a simple yet powerful throttling mechanism.

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