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Accumulo >> mail # user >> Table splitting


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Re: Table splitting
Check out o.a.a.server.util.LocalityCheck

-Eric
On Wed, Dec 12, 2012 at 1:17 PM, John Vines <[EMAIL PROTECTED]> wrote:

> 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:
>
>>
>> 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.
>>>>
>>>
>>>
>>