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https://issues.apache.org/jira/browse/HDFS-14084?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16753494#comment-16753494
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Pranay Singh edited comment on HDFS-14084 at 1/27/19 5:35 PM:
--------------------------------------------------------------

The above failures are related to changing the package details 
(org.apache.hadoop.hdfs) from org.apache.hadoop.hdfs.client.impl. The test 
fails as it uses classes that are only found in "org.apache.hadoop.hdfs" 
package, so I have moved TestClientMetrics.java under directory
 hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs.


was (Author: pranay_singh):
The above failures are related to changing the package details (below) from 
org.apache.hadoop.hdfs.client.impl. The test fails as it uses classes that are 
only found in "org.apache.hadoop.hdfs" package, so I have moved 
TestClientMetrics.java under directory
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs
package org.apache.hadoop.hdfs

> Need for more stats in DFSClient
> --------------------------------
>
>                 Key: HDFS-14084
>                 URL: https://issues.apache.org/jira/browse/HDFS-14084
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>    Affects Versions: 3.0.0
>            Reporter: Pranay Singh
>            Assignee: Pranay Singh
>            Priority: Minor
>             Fix For: 3.3.0
>
>         Attachments: HDFS-14084.001.patch, HDFS-14084.002.patch, 
> HDFS-14084.003.patch, HDFS-14084.004.patch, HDFS-14084.005.patch, 
> HDFS-14084.006.patch, HDFS-14084.007.patch, HDFS-14084.008.patch, 
> HDFS-14084.009.patch, HDFS-14084.010.patch, HDFS-14084.011.patch, 
> HDFS-14084.012.patch, HDFS-14084.013.patch, HDFS-14084.014.patch, 
> HDFS-14084.015.patch
>
>
> The usage of HDFS has changed from being used as a map-reduce filesystem, now 
> it's becoming more of like a general purpose filesystem. In most of the cases 
> there are issues with the Namenode so we have metrics to know the workload or 
> stress on Namenode.
> However, there is a need to have more statistics collected for different 
> operations/RPCs in DFSClient to know which RPC operations are taking longer 
> time or to know what is the frequency of the operation.These statistics can 
> be exposed to the users of DFS Client and they can periodically log or do 
> some sort of flow control if the response is slow. This will also help to 
> isolate HDFS issue in a mixed environment where on a node say we have Spark, 
> HBase and Impala running together. We can check the throughput of different 
> operation across client and isolate the problem caused because of noisy 
> neighbor or network congestion or shared JVM.
> We have dealt with several problems from the field for which there is no 
> conclusive evidence as to what caused the problem. If we had metrics or stats 
> in DFSClient we would be better equipped to solve such complex problems.
> List of jiras for reference:
> -------------------------
>  HADOOP-15538 HADOOP-15530 ( client side deadlock)



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