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https://issues.apache.org/jira/browse/HBASE-5757?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13283267#comment-13283267
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Hudson commented on HBASE-5757:
-------------------------------

Integrated in HBase-0.92-security #108 (See 
[https://builds.apache.org/job/HBase-0.92-security/108/])
    HBASE-5757 TableInputFormat should handle as many errors as possible (Jan 
Lukavsky) (Revision 1341205)

     Result = FAILURE
jmhsieh : 
Files : 
* /hbase/branches/0.92/CHANGES.txt
* 
/hbase/branches/0.92/src/main/java/org/apache/hadoop/hbase/mapred/TableRecordReaderImpl.java
* 
/hbase/branches/0.92/src/main/java/org/apache/hadoop/hbase/mapreduce/TableRecordReaderImpl.java
* 
/hbase/branches/0.92/src/test/java/org/apache/hadoop/hbase/mapred/TestTableInputFormat.java

                
> TableInputFormat should handle as many errors as possible
> ---------------------------------------------------------
>
>                 Key: HBASE-5757
>                 URL: https://issues.apache.org/jira/browse/HBASE-5757
>             Project: HBase
>          Issue Type: Bug
>          Components: mapred, mapreduce
>    Affects Versions: 0.90.6
>            Reporter: Jan Lukavsky
>            Assignee: Jan Lukavsky
>             Fix For: 0.90.7, 0.92.2, 0.96.0, 0.94.1
>
>         Attachments: 5757-trunk-v2.txt, HBASE-5757-trunk-r1341041.patch, 
> HBASE-5757.patch, HBASE-5757.patch, hbase-5757-92.patch
>
>
> Prior to HBASE-4196 there was different handling of IOExceptions thrown from 
> scanner in mapred and mapreduce API. The patch to HBASE-4196 unified this 
> handling so that if exception is caught a reconnect is attempted (without 
> bothering the mapred client). After that, HBASE-4269 changed this behavior 
> back, but in both mapred and mapreduce APIs. The question is, is there any 
> reason not to handle all errors that the input format can handle? In other 
> words, why not try to reissue the request after *any* IOException? I see the 
> following disadvantages of current approach
>  * the client may see exceptions like LeaseException and 
> ScannerTimeoutException if he fails to process all fetched data in timeout
>  * to avoid ScannerTimeoutException the client must raise 
> hbase.regionserver.lease.period
>  * timeouts for tasks is aready configured in mapred.task.timeout, so this 
> seems to me a bit redundant, because typically one needs to update both these 
> parameters
>  * I don't see any possibility to get rid of LeaseException (this is 
> configured on server side)
> I think all of these issues would be gone, if the DoNotRetryIOException would 
> not be rethrown. -On the other hand, handling errors in InputFormat has 
> disadvantage, that it may hide from the user some inefficiency. Eg. if I have 
> very big scanner.caching, and I manage to process only a few rows in timeout, 
> I will end up with single row being fetched many times (and will not be 
> explicitly notified about this). Could we solve this problem by adding some 
> counter to the InputFormat?-

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