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https://issues.apache.org/jira/browse/CASSANDRA-7245?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14011835#comment-14011835
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Benedict commented on CASSANDRA-7245:
-------------------------------------

Except that we sort in the Memtable/CLSM (and assert order at flush) by Token 
which is computed much earlier, whereas we write the raw key only.

> Out-of-Order keys with stress + CQL3
> ------------------------------------
>
>                 Key: CASSANDRA-7245
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-7245
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>            Reporter: Pavel Yaskevich
>            Assignee: T Jake Luciani
>             Fix For: 2.1 rc1
>
>         Attachments: 7245-v2.txt, 7245.txt
>
>
> We have been generating data (stress with CQL3 prepared) for CASSANDRA-4718 
> and found following problem almost in every SSTable generated (~200 GB of 
> data and 821 SSTables).
> We set up they keys to be 10 bytes in size (default) and population between 1 
> and 600000000.
> Once I ran 'sstablekeys' on the generated SSTable files I got following 
> exceptions:
> _There is a problem with sorting of normal looking keys:_
> 30303039443538353645
> 30303039443745364242
> java.io.IOException: Key out of order! DecoratedKey(-217680888487824985, 
> *30303039443745364242*) > DecoratedKey(-1767746583617597213, 
> *30303039443437454333*)
> 00000a30303033343933
> 37344400001388343933
> java.io.IOException: Key out of order! DecoratedKey(5440473860101999581, 
> *37344400001388343933*) > DecoratedKey(-7565486415339257200, 
> *30303033344639443137*)
> 30303033354244363031
> 30303033354133423742
> java.io.IOException: Key out of order! DecoratedKey(2687072396429900180, 
> *30303033354133423742*) > DecoratedKey(-7838239767410066684, 
> *30303033354145344534*)
> 30303034313442354137
> 30343136353633340000
> java.io.IOException: Key out of order! DecoratedKey(1516003874415400462, 
> *30343136353633340000*) > DecoratedKey(-9106177395653818217, 
> *30303034313333444238*)
> 30303035373044373435
> 30303035373044334631
> java.io.IOException: Key out of order! DecoratedKey(-3645715702154616540, 
> *30303035373044334631*) > DecoratedKey(-4296696226469000945, 
> *30303035373132364138*)
> _And completely different ones:_
> 30303041333745373543
> 7cd045c59a90d7587d8d
> java.io.IOException: Key out of order! DecoratedKey(-3595402345023230196, 
> *7cd045c59a90d7587d8d*) > DecoratedKey(-5146766422778260690, 
> *30303041333943303232*)
> 30303033323144444144
> 30303033323346343932
> java.io.IOException: Key out of order! DecoratedKey(7071845511166615635, 
> *30303033323346343932*) > DecoratedKey(5233296131921119414, 
> *53d83e00000012287e03*)
> 30303034314531374431
> 3806734b256c27e41ec2
> java.io.IOException: Key out of order! DecoratedKey(-7720474642702543193, 
> *3806734b256c27e41ec2*) > DecoratedKey(-8072288379146044663, 
> *30303034314136413343*)
> _And sometimes there is no problem at all:_
> 30303033353144463637
> 0000002a31b3b31a1c2f
> 5d616dd38211ebb5d6ec
> 44423645000013880000
> 00001388138844463744
> 30303033353143394343
> It's worth to mention that we have got 22 timeout exceptions but number of 
> out-of-order keys is much larger than that.



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