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https://issues.apache.org/jira/browse/HDFS-17577?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17874379#comment-17874379
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ASF GitHub Bot commented on HDFS-17577:
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ayushtkn commented on PR #6935:
URL: https://github.com/apache/hadoop/pull/6935#issuecomment-2294095406

   > This does not only happens in Flink, but also other engines like Spark 
etc. If I only sunmit a PR at FLINK side, the other engines' API (like SPARK, 
SPARK Structured stream) will not be able to use this feature and we need to 
rebuilt the whole computation project whenever we choose to use a new 
computation engine.
   
   That ain't our concern, We provide an interface to do things, If those 
engines want to leverage that functionality they can do that way.
   
   Those engines can't update their code or their are multiple clients or so 
doesn't justify bothering the hadoop side code




> Add Support for CreateFlag.NO_LOCAL_WRITE in File Creation to Manage Disk 
> Space and Network Load in Labeled YARN Nodes
> ----------------------------------------------------------------------------------------------------------------------
>
>                 Key: HDFS-17577
>                 URL: https://issues.apache.org/jira/browse/HDFS-17577
>             Project: Hadoop HDFS
>          Issue Type: New Feature
>          Components: dfsclient
>            Reporter: liang yu
>            Priority: Major
>              Labels: pull-request-available
>         Attachments: 6D939050-0BC4-4B17-A6A3-A1EBBD60338D.png
>
>
> {*}Description{*}: I am currently using Apache Flink to write files into 
> Hadoop. The Flink application runs on a labeled YARN queue. During operation, 
> it has been observed that the local disks on these labeled nodes get filled 
> up quickly, and the network load is significantly high. This issue arises 
> because Hadoop prioritizes writing files to the local node first, and the 
> number of these labeled nodes is quite limited.
>  
> {*}Problem{*}: The current behavior leads to inefficient disk space 
> utilization and high network traffic on these few labeled nodes, which could 
> potentially affect the performance and reliability of the application. As 
> shown in the picture, the host I circled have a average net_bytes_sent speed 
> 1.2GB/s while the others are just 50MB/s, this imbalance in network and disk 
> space nearly destroyed the whole cluster. 
> !6D939050-0BC4-4B17-A6A3-A1EBBD60338D.png|width=901,height=257!
>  
> {*}Implementation{*}: The implementation would involve adding an 
> configuration _dfs.client.write.no_local_write_ to support the 
> {{CreateFlag.NO_LOCAL_WRITE}} during the file creation process in Hadoop's 
> file system APIs. This will provide flexibility to applications like Flink 
> running in labeled queues to opt for non-local writes when necessary.
>  



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