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HBase >> mail # user >> Fixing badly distributed table manually.


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Re: Fixing badly distributed table manually.
Can you tell us the version of HBase you're using.

The following feature (per table region balancing) isn't in 0.92.x:
https://issues.apache.org/jira/browse/HBASE-3373

On table.jsp page, you should see region count per region server.

Cheers

On Tue, Sep 4, 2012 at 7:56 AM, David Koch <[EMAIL PROTECTED]> wrote:

> Hello,
>
> A couple of questions regarding balancing of a table's data in HBase.
>
> a) What is the easiest way to get an overview of how a table is distributed
> across regions of a cluster? I guess I could search .META. but I haven't
> figured out how to use filters from shell.
> b) What constitutes a "badly distributed" table and how can I re-balance
> manually?
> c) Is b) needed at all? I know that HBase does its balancing automatically
> behind the scenes.
>
> As for a) I tried running this script:
>
> https://github.com/Mendeley/hbase-scripts/blob/master/list_regions.rb
>
> like so:
>
> hbase org.jruby.Main ./list_regions.rb <_my_table>
>
> but I get
>
> ArgumentError: wrong number of arguments (1 for 2)
>   (root) at ./list_regions.rb:60
>
> If someone more proficient notices an obvious fix, I'd be glad to hear
> about it.
>
> Why do I ask? I have the impression that one of the tables on our HBase
> cluster is not well distributed. When running a Map Reduce job on this
> table, the load average on a single node is very high, whereas all other
> nodes are almost idling. It is the only table where this behavior is
> observed. Other Map Reduce jobs result in slightly elevated load averages
> on several machines.
>
> Thank you,
>
> /David
>