hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Raghu Angadi (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HADOOP-3124) DFS data node should not use hard coded 10 minutes as write timeout.
Date Tue, 15 Apr 2008 22:44:21 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-3124?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12589267#action_12589267

Raghu Angadi commented on HADOOP-3124:

Yes. This patch lowers the value to 8 min. I think 2 min is too short, because 1 min leads
to multiple false errors on the cluster I am using for HADOOP-3132. Currently we have this
timeout only to catch rare exceptions. I made sure that there is no changes to any logic in
the patch other than using regular sockets when the timeout is 0. This is good for 0.17.

> DFS data node should not use hard coded 10 minutes as write timeout.
> --------------------------------------------------------------------
>                 Key: HADOOP-3124
>                 URL: https://issues.apache.org/jira/browse/HADOOP-3124
>             Project: Hadoop Core
>          Issue Type: Bug
>          Components: dfs
>    Affects Versions: 0.17.0
>            Reporter: Runping Qi
>            Assignee: Raghu Angadi
>             Fix For: 0.18.0
>         Attachments: HADOOP-3124.patch, HADOOP-3124.patch
> This problem happens in 0.17 trunk
> I saw reducers waited 10 minutes for writing data to dfs and got timeout.
> The client retries again and timeouted after another 19 minutes.
> After looking into the code, it seems that the dfs data node uses 10 minutes as timeout
for wtiting data into the data node pipeline.
> I thing we have three issues:
> 1. The 10 minutes timeout value is too big for writing a chunk of data (64K) through
the data node pipeline.
> 2. The timeout value should not be hard coded.
> 3. Different datanodes in a pipeline should use different timeout values for writing
to the downstream.
> A reasonable one maybe (20 secs * numOfDataNodesInTheDownStreamPipe).
> For example, if the replication factor is 3, the client uses 60 secs, the first data
node use 40 secs, the second datanode use 20secs.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

View raw message