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HBase >> mail # user >> HBase scan performance decreases over time.


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David Koch 2012-11-03, 15:12
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Ted Yu 2012-11-03, 15:42
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David Koch 2012-11-03, 19:50
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Michael Segel 2012-11-05, 13:04
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Re: HBase scan performance decreases over time.
Where is this settings located?

Sent from my iPhone

On 5 בנוב 2012, at 15:05, Michael Segel <[EMAIL PROTECTED]> wrote:

> There's an HDFS bandwidth setting which is set to 10MB/s.
>
> Way too low for even 1GBe.
>
> Have you modified this setting yet?
>
> -Mike
>
> On Nov 3, 2012, at 2:50 PM, David Koch <[EMAIL PROTECTED]> wrote:
>
>> Hello Ted,
>>
>> We never initiate major compaction manually. I have not looked at I/O
>> balance between nodes in detail. We have noticed that after running for a
>> couple of weeks HBase seems to spend hours pushing blocks between nodes in
>> order to optimize things. We add data daily in one ~30gb push to several
>> tables. Sometimes nodes get added to the running system.
>>
>> Where can I get more information on how to carry out performance related
>> HBase administrative tasks?
>>
>> Thank you,
>>
>> /David
>>
>>
>> On Sat, Nov 3, 2012 at 4:42 PM, Ted Yu <[EMAIL PROTECTED]> wrote:
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>>> Can you tell us how often you run major compaction after the import ?
>>> Have you noticed imbalanced read / write requests in the cluster ? Meaning
>>> subset of region servers receive bulk of the writes.
>>>
>>> We do some manual movement of regions when the above happens.
>>>
>>> Cheers
>>>
>>> On Sat, Nov 3, 2012 at 8:12 AM, David Koch <[EMAIL PROTECTED]> wrote:
>>>
>>>> Hello,
>>>>
>>>> Every now and then we need to flatten our cluster and re-import all data
>>>> from log files (changes in data format, etc.) Afterwards we notice a
>>>> significant increase in scan performance. As data is added and shuffled
>>>> around between region servers, performance goes down again over time
>>> (say a
>>>> couple of weeks). Are there any routine operations that one should run
>>>> manually, or settings to activate in the HBase configuration to keep the
>>>> data well distributed? We use HBase 0.92 as part of a Cloudera4 cluster.
>>>>
>>>> Thank you,
>>>>
>>>> /David
>
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Leonid Fedotov 2012-11-05, 18:52
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Michael Segel 2012-11-05, 18:49
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Ted Yu 2012-11-03, 20:14