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https://issues.apache.org/jira/browse/CASSANDRA-4137?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Thibaut updated CASSANDRA-4137:
-------------------------------

    Priority: Major  (was: Critical)
    
> QUORUM Multiget RangeSliceQuery causes unnecessary writes to read entries
> -------------------------------------------------------------------------
>
>                 Key: CASSANDRA-4137
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-4137
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 0.8.9
>            Reporter: Thibaut
>
> From the mailing list:
> I created a new test keyspace and added 10 000 keys to it. The cluster has 3 
> machines, RF=3, read repair disabled (enabling it didn't change anything). 
> The keyspace doesn't contain any thumbstones. No keys were deleted.
> When I fetch a rangeslice through hector and set the consistency level to 
> quorum, according to cfstats (and also to the output files on the hd), 
> cassandra seems to execute a write request for each read I execute. The write 
> count in cfstats is increased when I execute the rangeslice function over the 
> same range again and again (without saving anything at all).
> If I set the consistency level to ONE or ALL, no writes are executed.
> I checked the writes on one machine. They increased by 2300 for each 
> iteration over the 10000 keys. I didn't check, but this probably corresponds 
> to the number of keys for which the machine is responsible.
> Code:
>                                 Keyspace ks = getConnection(cluster, 
> consistencylevel);
>                               RangeSlicesQuery<String, String, V> 
> rangeSlicesQuery = HFactory.createRangeSlicesQuery(ks, 
> StringSerializer.get(), StringSerializer.get(), s);
>                               rangeSlicesQuery.setColumnFamily(columnFamily);
>                               rangeSlicesQuery.setColumnNames(column);
>                               rangeSlicesQuery.setKeys(start, end);
>                               rangeSlicesQuery.setRowCount(maxrows);
>                               QueryResult<OrderedRows<String, String, V>> 
> result = rangeSlicesQuery.execute();
>                               return result.get();

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