hadoop-common-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "He Xiaoqiao (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HADOOP-16161) NetworkTopology#getWeightUsingNetworkLocation return unexpected result
Date Mon, 01 Apr 2019 12:51:04 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-16161?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16806728#comment-16806728
] 

He Xiaoqiao commented on HADOOP-16161:
--------------------------------------

Thanks [~elgoiri] for your reviews,  [^HADOOP-16161.007.patch] add new unit test to coverage
#sortLocatedBlocks.

> NetworkTopology#getWeightUsingNetworkLocation return unexpected result
> ----------------------------------------------------------------------
>
>                 Key: HADOOP-16161
>                 URL: https://issues.apache.org/jira/browse/HADOOP-16161
>             Project: Hadoop Common
>          Issue Type: Bug
>          Components: net
>            Reporter: He Xiaoqiao
>            Assignee: He Xiaoqiao
>            Priority: Major
>         Attachments: HADOOP-16161.001.patch, HADOOP-16161.002.patch, HADOOP-16161.003.patch,
HADOOP-16161.004.patch, HADOOP-16161.005.patch, HADOOP-16161.006.patch, HADOOP-16161.007.patch
>
>
> Consider the following scenario:
> 1. there are 4 slaves and topology like:
> Rack: /IDC/RACK1
>    hostname1
>    hostname2
> Rack: /IDC/RACK2
>    hostname3
>    hostname4
> 2. Reader from hostname1, and calculate weight between reader and [hostname1, hostname3,
hostname4] by #getWeight, and their corresponding values are [0,4,4]
> 3. Reader from client which is not in the topology, and in the same IDC but in none rack
of the topology, and calculate weight between reader and [hostname1, hostname3, hostname4]
by #getWeightUsingNetworkLocation, and their corresponding values are [2,2,2]
> 4. Other different Reader can get the similar results.
> The weight result for case #3 is obviously not the expected value, the truth is [4,4,4].
this issue may cause reader not really following arrange: local -> local rack -> remote
rack. 
> After dig the detailed implement, the root cause is #getWeightUsingNetworkLocation only
calculate distance between Racks rather than hosts.
> I think we should add constant 2 to correct the weight of #getWeightUsingNetworkLocation.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

---------------------------------------------------------------------
To unsubscribe, e-mail: common-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: common-issues-help@hadoop.apache.org


Mime
View raw message