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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 15:58:57 GMT
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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