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Date: Sat, 3 Nov 2012 08:42:42 -0700
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 <CALte62z+pb8mFapmrkwGzxu6KgEznc7SYXi=RxT-9gaAHb6OpA@mail.gmail.com>
Subject: Re: HBase scan performance decreases over time.
From: Ted Yu <yuzhihong@gmail.com>
To: user@hbase.apache.org
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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 <ogdude@googlemail.com> 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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