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HBase, mail # user - Compaction problem


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Re: Compaction problem
Asaf Mesika 2013-03-26, 21:26
1st thing I would do to find the bottleneck it so benchmark HDFS solo performance.
Create a 16GB file (using dd) which is x2 your memory and run "time hadoop fs -copyFromLocal yourFile.txt /tmp/a.txt"
Tell us what is the speed of this file copy in MB/sec.
On Mar 22, 2013, at 4:44 PM, tarang dawer <[EMAIL PROTECTED]> wrote:

> Hi
> As per my use case , I have to write around 100gb data , with a ingestion
> speed of around 200 mbps. While writing , i am getting a performance hit by
> compaction , which adds to the delay.
> I am using a 8 core machine with 16 gb RAM available., 2 Tb hdd 7200RPM.
> Got some idea from the archives and  tried pre splitting the regions ,
> configured HBase with following parameters(configured the parameters in a
> haste , so please guide me if anything's out of order) :-
>
>
>        <property>
>                <name>hbase.hregion.memstore.block.multiplier</name>
>                <value>4</value>
>        </property>
>        <property>
>                 <name>hbase.hregion.memstore.flush.size</name>
>                 <value>1073741824</value>
>        </property>
>
>        <property>
>                <name>hbase.hregion.max.filesize</name>
>                <value>1073741824</value>
>        </property>
>        <property>
>                <name>hbase.hstore.compactionThreshold</name>
>                <value>5</value>
>        </property>
>        <property>
>              <name>hbase.hregion.majorcompaction</name>
>                  <value>0</value>
>        </property>
>        <property>
>                <name>hbase.hstore.blockingWaitTime</name>
>                <value>30000</value>
>        </property>
>         <property>
>                 <name>hbase.hstore.blockingStoreFiles</name>
>                 <value>200</value>
>         </property>
>
>  <property>
>        <name>hbase.regionserver.lease.period</name>
>        <value>3000000</value>
>  </property>
>
>
> but still m not able to achieve the optimal rate , getting around 110 mbps.
> Need some optimizations ,so please could you help out ?
>
> Thanks
> Tarang Dawer
>
>
>
>
>
> On Fri, Mar 22, 2013 at 6:05 PM, Jean-Marc Spaggiari <
> [EMAIL PROTECTED]> wrote:
>
>> Hi Tarang,
>>
>> I will recommand you to take a look at the list archives first to see
>> all the discussions related to compaction. You will found many
>> interesting hints and tips.
>>
>>
>> http://search-hadoop.com/?q=compactions&fc_project=HBase&fc_type=mail+_hash_+user
>>
>> After that, you will need to provide more details regarding how you
>> are using HBase and how the compaction is impacting you.
>>
>> JM
>>
>> 2013/3/22 tarang dawer <[EMAIL PROTECTED]>:
>>> Hi
>>> I am using HBase 0.94.2 currently. While using it  , its write
>> performance,
>>> due to compaction is being affeced by compaction.
>>> Please could you suggest some quick tips in relation to how to deal with
>> it
>>> ?
>>>
>>> Thanks
>>> Tarang Dawer
>>