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From Thibaut Britz <thibaut.br...@trendiction.com>
Subject Re: cassandra 0.8.7 + hector 0.8.3: All Quorum reads result in writes?
Date Wed, 11 Apr 2012 16:56:45 GMT
Fixed in  https://issues.apache.org/jira/browse/CASSANDRA-3843



On Wed, Apr 11, 2012 at 5:58 PM, Thibaut Britz <
thibaut.britz@trendiction.com> wrote:

> We have read repair disabled (0.0).
>
> Even if this would be the case, this also doesn't explain why the writes
> are executed again and again when going over the same range again and again.
>
> The keyspace is new, it doesn't contain any thumbstones and only 10000
> keys.
>
>
>
> On Wed, Apr 11, 2012 at 5:52 PM, R. Verlangen <robin@us2.nl> wrote:
>
>> Are you sure this isn't read-repair?
>> http://wiki.apache.org/cassandra/ReadRepair
>>
>>
>> 2012/4/11 Thibaut Britz <thibaut.britz@trendiction.com>
>>
>>> Also executing the same multiget rangeslice query over the same range
>>> again will trigger the same writes again and again.
>>>
>>> On Wed, Apr 11, 2012 at 5:41 PM, Thibaut Britz <
>>> thibaut.britz@trendiction.com> wrote:
>>>
>>>> Hi,
>>>>
>>>> I just diagnosted this strange behavior:
>>>>
>>>> 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 consitency level to ONE, no writes are executed.
>>>>
>>>> How can I disable this? Why are the records rewritten each time, even
>>>> though I don't want them to be rewritten?
>>>>
>>>> Thanks,
>>>> Thibaut.
>>>>
>>>>
>>>> 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();
>>>>
>>>>
>>>>
>>>>
>>>
>>
>>
>> --
>> With kind regards,
>>
>> Robin Verlangen
>> www.robinverlangen.nl
>>
>>
>

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