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HBase, mail # user - Region hot spotting


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Re: Region hot spotting
Doug Meil 2012-11-21, 18:52

Hi there-

If he's using monotonically increasing keys the pre splits won't help
because the same region is going to get all the writes.

http://hbase.apache.org/book.html#rowkey.design

On 11/21/12 12:33 PM, "Suraj Varma" <[EMAIL PROTECTED]> wrote:

>Ajay:
>Why would you not want to specify splits while creating table? If your
>0-10 prefix is at random ... why not pre-split with that?
>
>Without presplitting, as Ram says, you cannot avoid region hotspotting
>until table starts automatic splits.
>--S
>
>On Wed, Nov 21, 2012 at 3:46 AM, Ajay Bhosle
><[EMAIL PROTECTED]> wrote:
>> Thanks for your comments,
>>
>> I am already prefixing the timestamp with integer in range of 1..10,
>>also
>> the hbase.hregion.max.filesize is defined as 256 MB. Still it is hot
>> spotting.
>>
>> Thanks
>> Ajay
>>
>> -----Original Message-----
>> From: ramkrishna vasudevan [mailto:[EMAIL PROTECTED]]
>> Sent: Wednesday, November 21, 2012 2:14 PM
>> To: [EMAIL PROTECTED]
>> Subject: Re: Region hot spotting
>>
>> Hi
>> This link is pretty much useful.  But still there too it says if you
>>dont
>> pre split you need to wait for the salting to help you from hotspotting
>> till the region gets splitted.
>>
>> Mohammad just pointing this to say the usefulness of presplitting
>> definitely your's is a good pointer to Ajay. :)
>>
>> Regards
>> Ram
>>
>> On Wed, Nov 21, 2012 at 1:59 PM, Mohammad Tariq <[EMAIL PROTECTED]>
>>wrote:
>>
>>> Hello Ajay,
>>>
>>>  You can use 'salting' if you don't want to presplit your table. You
>>>might
>>> this link useful :
>>>
>>>
>>
>>http://blog.sematext.com/2012/04/09/hbasewd-avoid-regionserver-hotspottin
>>g-d
>> espite-writing-records-with-sequential-keys/
>>>
>>> HTH
>>>
>>> Regards,
>>>     Mohammad Tariq
>>>
>>>
>>>
>>> On Wed, Nov 21, 2012 at 1:49 PM, ramkrishna vasudevan <
>>> [EMAIL PROTECTED]> wrote:
>>>
>>> > Hotspotting is bound to happen until the region starts splitting and
>> gets
>>> > assigned to diff region servers.
>>> >
>>> > Regards
>>> > Ram
>>> >
>>> > On Wed, Nov 21, 2012 at 12:49 PM, Ajay Bhosle
>>> > <[EMAIL PROTECTED]>wrote:
>>> >
>>> > > Hi,
>>> > >
>>> > >
>>> > >
>>> > > I am inserting some data in hbase which is getting hot spotted in a
>>> > > particular server. The format of the row key is (0 or
>>> > > 1)|[timestamp]_[sequence].  Basically I want to add log
>>>information to
>>> > > hbase
>>> > > and search the records based on range of dates.
>>> > >
>>> > >
>>> > >
>>> > > Can someone suggest any configuration changes or any ideas on how
>>>the
>>> row
>>> > > key should be design. I do not want to specify the splits while
>>> creating
>>> > > table.
>>> > >
>>> > >
>>> > >
>>> > > Thanks
>>> > >
>>> > > Ajay
>>> > >
>>> > >
>>> > >
>>> > >
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