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Accumulo, mail # user - Table splitting


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Mathias Herberts 2012-12-11, 14:32
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William Slacum 2012-12-11, 14:37
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ameet kini 2012-12-12, 18:08
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Re: Table splitting
John Vines 2012-12-12, 18:17
When a file gets written to hdfs, there is a guarantee the file is local as
long as that systems disks are not full. Accumulo does not have a locality
guarantee as tablets will migrate on occasion. However, as data is added,
major compactions will occur which will restore locality.
On Dec 12, 2012 1:09 PM, "ameet kini" <[EMAIL PROTECTED]> wrote:

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> Along these lines....
>
> Can someone help me understand how tablets map to files on disk in HDFS?
> From what I understand, after a compaction, there may be one (or more?)
> files on HDFS for a given tablet. Each file can consist of multiple HDFS
> blocks. Does Accumulo guarantee that the tablet serving a given data range
> finds all its blocks locally? If so, how does it keep this guarantee?
> Wouldn't HDFS distribute these blocks around based on HDFS balancing
> strategy?
>
> Thanks,
> Ameet
>
> On Tue, Dec 11, 2012 at 9:37 AM, William Slacum <
> [EMAIL PROTECTED]> wrote:
>
>> Tablets will split automatically, down to the granularity of a row.
>>
>>
>> On Tue, Dec 11, 2012 at 9:32 AM, Mathias Herberts <
>> [EMAIL PROTECTED]> wrote:
>>
>>> Hi,
>>>
>>> I've read the user manual for v1.4.2 and I have not seen any mention of
>>> automatic tablet splitting. Is there such a thing in Accumulo or is
>>> pre-splitting the only way to split a table?
>>>
>>> Thanks,
>>>
>>> Mathias.
>>>
>>
>>
>
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Eric Newton 2012-12-12, 18:18
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ameet kini 2012-12-12, 18:27
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Eric Newton 2012-12-12, 18:29
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ameet kini 2012-12-12, 18:32
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Eric Newton 2012-12-12, 18:36
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ameet kini 2012-12-12, 18:45
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Mathias Herberts 2012-12-11, 14:38
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Keith Turner 2012-12-11, 14:58
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Mathias Herberts 2012-12-11, 15:01