[jira] [Commented] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-14 Thread Ajay Sachdev (JIRA)

[ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16474674#comment-16474674
 ] 

Ajay Sachdev commented on HDFS-13398:
-

Hi Rushabh,

Thats a good question. As you may know FJP is very critical for multi-core 
systems and it forks large tasks into smaller subtasks and then joins (waits) 
individual results to form final result (Divide and Conquer approach). We tried 
different number for parallelism (ie number of threads) in ForkJoinPool 
framework such as 8, 16, 32 and 64. The use case was a directory/file hierarchy 
structure of 40K+ and a nested tree-level. In this scenario we were able to 
demonstrate that a numberOfThreads=32 was ideal configuration. So our tests 
were based off these variables.

FsShell commands (single threaded approach) -

ls -R -> 12 mins

du -> 14 mins

count -> 14 mins

 

FsShell commands (FJP approach) -

ls -R -> 3 mins

du -> 2 mins

count -> 9 mins

 

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, HDFS-13398.002.patch, 
> parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Commented] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-14 Thread Ajay Sachdev (JIRA)

[ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16474335#comment-16474335
 ] 

Ajay Sachdev commented on HDFS-13398:
-

Hi Yiqun,

Thanks for taking the time to take a look at the patch. I have also uploaded 
the 2nd version of the patch against apache trunk. I would appreciate if you 
could provide some feedback against that version as well. This patch is 
intended for our customer which is using ViPRFS interface and they only want to 
run -ls -R/-du and count commands of FsShell. I agree that if there is any 
mutable shared state that any of sub-commands such as usagesTable in 
FsUsage.java class then we will wrap synchronized block around it to make it 
thread-safe. As a long term solution we would like to optimize all FsShell 
commands to take use of this ForkJoin Pool Framework and then all sub-commands 
implementation can ensure that any shared state are thread-safe.

 

Thanks

Ajay

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, HDFS-13398.002.patch, 
> parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Commented] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-14 Thread Ajay Sachdev (JIRA)

[ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16474147#comment-16474147
 ] 

Ajay Sachdev commented on HDFS-13398:
-

Hi Mukul,

I have attached the new patch to JIRA.

 

Cheers,

Ajay

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, HDFS-13398.002.patch, 
> parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Updated] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-14 Thread Ajay Sachdev (JIRA)

 [ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ajay Sachdev updated HDFS-13398:

Attachment: HDFS-13398.002.patch

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, HDFS-13398.002.patch, 
> parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Issue Comment Deleted] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-12 Thread Ajay Sachdev (JIRA)

 [ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ajay Sachdev updated HDFS-13398:

Comment: was deleted

(was: HDFS-13398.002.patch)

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Commented] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-12 Thread Ajay Sachdev (JIRA)

[ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16473104#comment-16473104
 ] 

Ajay Sachdev commented on HDFS-13398:
-

HDFS-13398.002.patch

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Comment Edited] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-11 Thread Ajay Sachdev (JIRA)

[ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16472582#comment-16472582
 ] 

Ajay Sachdev edited comment on HDFS-13398 at 5/11/18 8:14 PM:
--

I have attached apache hadoop trunk multithreading diff. Please take a look at 
code review and provide comments.

 

Thanks

Ajay


was (Author: ajaynmalu23):
I have attached apache hadoop trunk multithreading diff. Please take a look at 
code review and provide comments.

 

Thanks

Ajay

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Commented] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-11 Thread Ajay Sachdev (JIRA)

[ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16472582#comment-16472582
 ] 

Ajay Sachdev commented on HDFS-13398:
-

I have attached apache hadoop trunk multithreading diff. Please take a look at 
code review and provide comments.

 

Thanks

Ajay

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Updated] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-02 Thread Ajay Sachdev (JIRA)

 [ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ajay Sachdev updated HDFS-13398:

Attachment: HDFS-13398.001.patch

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Commented] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-05-02 Thread Ajay Sachdev (JIRA)

[ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16461122#comment-16461122
 ] 

Ajay Sachdev commented on HDFS-13398:
-

Hi Mukul/Arpit,

Sorry for late response. We would like to get a formal review process for this 
patch before we deploy on customer site. I will work on items #3 and #4 above. 
Also I was unable to find trunk branch in 

[https://github.com/hortonworks/hadoop-release.] So we have used HDP tag -

HDP-2.6.2.0-205-tag

I have also attached the patch against this tag. I would appreciate if you 
could take a look at code and get a review as well.

 

Thanks

Ajay[^HDFS-13398.001.patch]

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Assignee: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: HDFS-13398.001.patch, parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Updated] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-04-10 Thread Ajay Sachdev (JIRA)

 [ 
https://issues.apache.org/jira/browse/HDFS-13398?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ajay Sachdev updated HDFS-13398:

Attachment: parallelfsPatch

> Hdfs recursive listing operation is very slow
> -
>
> Key: HDFS-13398
> URL: https://issues.apache.org/jira/browse/HDFS-13398
> Project: Hadoop HDFS
>  Issue Type: Bug
>  Components: hdfs
>Affects Versions: 2.7.1
> Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
> (Object Store).
>Reporter: Ajay Sachdev
>Priority: Major
> Fix For: 2.7.1
>
> Attachments: parallelfsPatch
>
>
> The hdfs dfs -ls -R command is sequential in nature and is very slow for a 
> HCFS system. We have seen around 6 mins for 40K directory/files structure.
> The proposal is to use multithreading approach to speed up recursive list, du 
> and count operations.
> We have tried a ForkJoinPool implementation to improve performance for 
> recursive listing operation.
> [https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]
> commit id : 
> 82387c8cd76c2e2761bd7f651122f83d45ae8876
> Another implementation is to use Java Executor Service to improve performance 
> to run listing operation in multiple threads in parallel. This has 
> significantly reduced the time to 40 secs from 6 mins.
>  
>  



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[jira] [Created] (HDFS-13398) Hdfs recursive listing operation is very slow

2018-04-04 Thread Ajay Sachdev (JIRA)
Ajay Sachdev created HDFS-13398:
---

 Summary: Hdfs recursive listing operation is very slow
 Key: HDFS-13398
 URL: https://issues.apache.org/jira/browse/HDFS-13398
 Project: Hadoop HDFS
  Issue Type: Bug
  Components: hdfs
Affects Versions: 2.7.1
 Environment: HCFS file system where HDP 2.6.1 is connected to ECS 
(Object Store).
Reporter: Ajay Sachdev
 Fix For: 2.7.1


The hdfs dfs -ls -R command is sequential in nature and is very slow for a HCFS 
system. We have seen around 6 mins for 40K directory/files structure.

The proposal is to use multithreading approach to speed up recursive list, du 
and count operations.

We have tried a ForkJoinPool implementation to improve performance for 
recursive listing operation.

[https://github.com/jasoncwik/hadoop-release/tree/parallel-fs-cli]

commit id : 

82387c8cd76c2e2761bd7f651122f83d45ae8876

Another implementation is to use Java Executor Service to improve performance 
to run listing operation in multiple threads in parallel. This has 
significantly reduced the time to 40 secs from 6 mins.

 

 



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