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Chukwa >> mail # user >> Seeing duplicate entries


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Re: Seeing duplicate entries
Eric, I'm also curious about how the HBase integration works. Do you
have time to write something up on it? I'm interested in the
possibility of extending what's there to write my own custom data into
HBase from a collector, while said data also continues through to HDFS
as it does currently.
On Fri, Oct 22, 2010 at 5:21 PM, Corbin Hoenes <[EMAIL PROTECTED]> wrote:
> Eric in chukwa 0.5 is hbase the final store instead of hdfs?  What format
> will the hbase data be in (e.g. A chukwarecord object ? Something user
> configurable? )
>
> Sent from my iPhone
>
> On Oct 22, 2010, at 8:48 AM, Eric Yang <[EMAIL PROTECTED]> wrote:
>
>> Hi Matt,
>>
>> This is expected in Chukwa archives.  When agent is unable to post to
>> the collector, it will retry to post the same data again to another
>> collector or retrys with the same collector when no other collector is
>> available.  Collector may have data written without proper acknowledge
>> back to agent in high load situation.  Chukwa philosophy is to retry
>> until receiving acknowledgement.  Duplicated data filter will be
>> treated after data has been received.
>>
>> The duplication filtering in Chukwa 0.3.0 depends on data loading to
>> mysql.  The same primary key will update to the same row to remove
>> duplicates.  It is possible to build a duplication detection process
>> prior to demux which filter data based on sequence id + data type +
>> csource (host), but this hasn't been implemented because primary key
>> update method works well for my use case.
>>
>> In Chukwa 0.5, we are treating duplication the same as in Chukwa 0.3,
>> where it will replace any duplicated row in HBase base on Timestamp +
>> HBase row key.
>>
>> regards,
>> Eric
>>
>> On Thu, Oct 21, 2010 at 8:22 PM, Matt Davies <[EMAIL PROTECTED]> wrote:
>>>
>>> Hey everyone,
>>>
>>> I have a situation where I'm seeing duplicated data downstream before the
>>> demux process. It appears this happens during high system loads and we are
>>> still using the 0.3.0 series.
>>>
>>> So, we have validated that there is a single, unique entry in our source
>>> file which then shows up a random amount of times before we see it in demux.
>>> So, it appears that there is duplication happening somewhere between the
>>> agent and collector.
>>>
>>> Has anyone else seen this? Any ideas as to why we are seeing this during
>>> high system loads, but not during lower loads.
>>>
>>> TIA,
>>> Matt
>>>
>>>
>