@Malith
What do you mean as a generic tool?

@Ramith
I think that only works with Cassandra 2.0 onwards (If I'm not mistaken)
and BAM uses Cassandra 1.x versions. That was the initial issue.

On Wed, Sep 16, 2015 at 1:18 PM, Ramith Jayasinghe <[email protected]> wrote:

> so,
>
> http://docs.datastax.com/en/drivers/java/2.0/com/datastax/driver/core/ResultSet.html#fetchMoreResults()
>  doesn't work for you?
>
> On Wed, Sep 16, 2015 at 12:22 PM, Malith Dhanushka <[email protected]>
> wrote:
>
>> Hi Sachith,
>>
>> +1 for using Hector and this will be a handy utility tool for DAS as
>> well. Because anyone who has Cassandra raw data can use this tool to
>> persist them in any file store facilitated by DAL. Given the fact, is it
>> worth the effort implementing this as a generic tool? WDUT?
>>
>> Thanks,
>> Malith
>>
>> On Wed, Sep 16, 2015 at 10:54 AM, Sachith Withana <[email protected]>
>> wrote:
>>
>>> Hi all,
>>>
>>> DAS migration tool is used to migrate the data from BAM deployments to
>>> DAS.
>>>
>>> Basically how it works is, it reads the records from Cassandra column
>>> families (of BAM) and inserts them to DAS analytics tables at the Data
>>> Access Layer (DAL) level.
>>>
>>> BAM uses Cassandra 1.x versions and the previous iteration of the tool
>>> was using CQL to get all the records from a given column family and insert
>>> them to DAL.
>>>
>>> But for large amounts of records read from BAM caused CQL to throw an
>>> OutOfMemory exception from the GC, since CQL is trying to load all the
>>> records to memory ( using select * from *tableName* ).
>>>
>>> Therefore we had to introduce pagination support by rewriting the
>>> migration tool using the Hector Driver.
>>>
>>> Now the hector based implementation reads in records batch-wise ( the
>>> batch size is configurable) and inserts to DAL thus taking out the
>>> possibility of running out of memory.
>>>
>>> Thanks,
>>> Sachith
>>> --
>>> Sachith Withana
>>> Software Engineer; WSO2 Inc.; http://wso2.com
>>> E-mail: sachith AT wso2.com
>>> M: +94715518127
>>> Linked-In: <http://goog_416592669>
>>> https://lk.linkedin.com/in/sachithwithana
>>>
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>>>
>>>
>>
>>
>> --
>> Malith Dhanushka
>> Senior Software Engineer - Data Technologies
>> *WSO2, Inc. : wso2.com <http://wso2.com/>*
>> *Mobile*          : +94 716 506 693
>>
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>>
>
>
> --
> Ramith Jayasinghe
> Technical Lead
> WSO2 Inc., http://wso2.com
> lean.enterprise.middleware
>
> E: [email protected]
> P: +94 777542851
>
>
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>


-- 
Sachith Withana
Software Engineer; WSO2 Inc.; http://wso2.com
E-mail: sachith AT wso2.com
M: +94715518127
Linked-In: <http://goog_416592669>https://lk.linkedin.com/in/sachithwithana
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