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From Dave Brosius <dbros...@mebigfatguy.com>
Subject Re: Secondary Index Storage
Date Fri, 23 Aug 2013 13:50:58 GMT
the location is loaded from the

cassandra.yaml,

specifically the entry

data_file_directories

This is loaded into the class

Config.java

using 3rdparty library snakeyaml


On 08/23/2013 06:34 AM, Nipuni Piyabasi Perera wrote:
> Hi,
>
> Ok, so if I want to make it separate and test, where should I refer? From
> where the keyspace refer to the location "/var/lib/cassandra/data". I have
> debug the code, and could see some variables (e.g jdk location etc) can be
> accessed from :
>
> System.getProperty("");
>
> But this does not contain the disk location to keyspace.
>
> Thanks,
> Nipuni
>
>
> On Fri, Aug 23, 2013 at 9:52 AM, Jonathan Ellis <jbellis@gmail.com> wrote:
>
>> Sorry, Aleksey pointed out that the index directory isn't separate from the
>> "parent" table.  Probably so that we can snapshot them both together, which
>> is why the separate config in .yaml doesn't make sense either.
>>
>>
>> On Thu, Aug 22, 2013 at 11:07 PM, Jonathan Ellis <jbellis@gmail.com>
>> wrote:
>>
>>> You can already symlink the index directory anywhere you like.  I'm not
>>> convinced that special-casing indexes is a good approach in general vs
>>> looking at performance of all tables.
>>>
>>>
>>> On Thu, Aug 22, 2013 at 8:16 PM, Nipuni Piyabasi Perera <
>>> nipuni880917@gmail.com> wrote:
>>>
>>>> Hi,
>>>>
>>>> I need to do a secondary index access improvement with a little
>>>> modification to Cassandra. I could see in [1], that the performance of
>>>> secondary index querying can be increased via splitting the column
>> family
>>>> data and secondary index data.
>>>> Currently Cassandra saves keyspace data and secondary indices data in
>>>> "var/lib/cassandra/data/".
>>>> According to my understanding the data saves in the
>>>> "data_file_directories"
>>>> location of conf/cassandra.yaml file. If I can enter new variable into
>>>> "cassandra.yaml" file and address it in the place where Cassandra stores
>>>> secondary indexes, this can be fixed.
>>>>
>>>> Can anyone give some guidance regarding this improvement.
>>>>
>>>> [1] https://issues.apache.org/jira/browse/CASSANDRA-5502
>>>>
>>>> Thanks,
>>>> Nipuni
>>>>
>>>> --
>>>> Nipuni Piyabasi Perera
>>>> Undergraduate
>>>> Department of Computer Science And Engineering
>>>> University of Moratuwa
>>>> Sri Lanka
>>>>
>>>
>>>
>>> --
>>> Jonathan Ellis
>>> Project Chair, Apache Cassandra
>>> co-founder, http://www.datastax.com
>>> @spyced
>>>
>>
>>
>> --
>> Jonathan Ellis
>> Project Chair, Apache Cassandra
>> co-founder, http://www.datastax.com
>> @spyced
>>
>
>


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