You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@cassandra.apache.org by "Jonathan Ellis (JIRA)" <ji...@apache.org> on 2010/06/25 20:52:53 UTC

[jira] Updated: (CASSANDRA-1042) ColumnFamilyRecordReader returns duplicate rows

     [ https://issues.apache.org/jira/browse/CASSANDRA-1042?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Jonathan Ellis updated CASSANDRA-1042:
--------------------------------------

    Fix Version/s: 0.6.4
                       (was: 0.6.3)

> ColumnFamilyRecordReader returns duplicate rows
> -----------------------------------------------
>
>                 Key: CASSANDRA-1042
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-1042
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Hadoop
>    Affects Versions: 0.6
>            Reporter: Joost Ouwerkerk
>            Assignee: Jeremy Hanna
>             Fix For: 0.6.4
>
>         Attachments: Cassandra-1042-0_6-branch.patch.txt, CASSANDRA-1042-trunk.patch.txt, cassandra.tar.gz
>
>
> There's a bug in ColumnFamilyRecordReader that appears when processing a single split (which happens in most tests that have small number of rows), and potentially in other cases.  When the start and end tokens of the split are equal, duplicate rows can be returned.
> Example with 5 rows:
> token (start and end) = 53193025635115934196771903670925341736
> Tokens returned by first get_range_slices iteration (all 5 rows):
>  16955237001963240173058271559858726497
>  40670782773005619916245995581909898190
>  99079589977253916124855502156832923443
>  144992942750327304334463589818972416113
>  166860289390734216023086131251507064403
> Tokens returned by next iteration (first token is last token from
> previous, end token is unchanged)
>  16955237001963240173058271559858726497
>  40670782773005619916245995581909898190
> Tokens returned by final iteration  (first token is last token from
> previous, end token is unchanged)
>  [] (empty)
> In this example, the mapper has processed 7 rows in total, 2 of which
> were duplicates.

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