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Date: Wed, 21 Nov 2012 11:08:00 +0000 (UTC)
From: "Jonathan Ellis (JIRA)" <jira@apache.org>
To: commits@cassandra.apache.org
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Subject: [jira] [Commented] (CASSANDRA-2388) ColumnFamilyRecordReader fails
 for a given split because a host is down, even if records could reasonably
 be read from other replica.
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    [ https://issues.apache.org/jira/browse/CASSANDRA-2388?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13501857#comment-13501857 ] 

Jonathan Ellis commented on CASSANDRA-2388:
-------------------------------------------

Jake's plan above seems like a reasonable approach, but let me back up a step.  I'm just not convinced that the problem we're trying to solve is a real one.  Why do we want to suck a split's worth of data off-node?  If it's because you don't have TackTrackers running on your Cassandra nodes, well, go fix that.

If it's because Hadoop has created too many tasks and all the local replicas have their task queue full, won't assigning it to a non-local TT just cause more contention, than waiting for a local slot to free up?
                
> ColumnFamilyRecordReader fails for a given split because a host is down, even if records could reasonably be read from other replica.
> -------------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: CASSANDRA-2388
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-2388
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Hadoop
>    Affects Versions: 0.6
>            Reporter: Eldon Stegall
>            Assignee: Mck SembWever
>            Priority: Minor
>              Labels: hadoop, inputformat
>             Fix For: 1.1.7
>
>         Attachments: 0002_On_TException_try_next_split.patch, CASSANDRA-2388-addition1.patch, CASSANDRA-2388-extended.patch, CASSANDRA-2388.patch, CASSANDRA-2388.patch, CASSANDRA-2388.patch, CASSANDRA-2388.patch
>
>
> ColumnFamilyRecordReader only tries the first location for a given split. We should try multiple locations for a given split.

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