[jira] [Comment Edited] (HBASE-16212) Many connections to datanode are created when doing a large scan

["Zhihua Deng (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HBASE-16212?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15383516#comment-15383516 ] 

Zhihua Deng edited comment on HBASE-16212 at 7/19/16 3:11 AM:
--------------------------------------------------------------

Test it on my cluster, a hmaster with two regionservers based on hbase-1.1.2, it works. Further test should carry on the master brunch


was (Author: dengzh):
Test it on my cluster, a hmaster with two regionservers based on hbase-1.1.2, it works. Further test should carry on the master brunch

> Many connections to datanode are created when doing a large scan 
> -----------------------------------------------------------------
>
>                 Key: HBASE-16212
>                 URL: https://issues.apache.org/jira/browse/HBASE-16212
>             Project: HBase
>          Issue Type: Improvement
>    Affects Versions: 1.1.2
>            Reporter: Zhihua Deng
>         Attachments: HBASE-16212.patch, HBASE-16212.v2.patch, regionserver-dfsinputstream.log
>
>
> As described in https://issues.apache.org/jira/browse/HDFS-8659, the datanode is suffering from logging the same repeatedly. Adding log to DFSInputStream, it outputs as follows:
> 2016-07-10 21:31:42,147 INFO  [B.defaultRpcServer.handler=22,queue=1,port=16020] hdfs.DFSClient: DFSClient_NONMAPREDUCE_1984924661_1 seek DatanodeInfoWithStorage[10.130.1.29:50010,DS-086bc494-d862-470c-86e8-9cb7929985c6,DISK] for BP-360285305-10.130.1.11-1444619256876:blk_1109360829_35627143. pos: 111506876, targetPos: 111506843
>  ...
> As the pos of this input stream is larger than targetPos(the pos trying to seek), A new connection to the datanode will be created, the older one will be closed as a consequence. When the wrong seeking ops are large, the datanode's block scanner info message is spamming logs, as well as many connections to the same datanode will be created.
> hadoop version: 2.7.1



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)