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Re: Unbalanced region server
Thanks Bryan.

Here is the regions count:

1: 2616
2: 2620
3: 2623
4: 2617
5: 2617

The skew is in Node 2 where we have the space issue (double the size of
other 4 nodes).

On Mon, Apr 23, 2012 at 7:50 PM, Bryan Beaudreault <[EMAIL PROTECTED]
> wrote:

> Do all nodes have the same number of regions?  If not you may not have the
> balancer on.  You can turn it on using balancer_switch true in the hbase
> shell.  The balancer also doesn't run if there is a region stuck in
> transition.  In this case if your data is growing rapidly I have seen
> regionservers become lopsided until I could clean up the stuck region and
> re-enable the balancer.
>
> Finally, depending on your version of hbase, the balancer only tries to
> keep the number of regions similar across all regionservers.  If you have
> tables of different max region sizes I could imagine a case where one
> region server unluckily is hosting more regions from the table with larger
> region sizes.  This also might explain the imbalance in requests, if one of
> your tables gets more traffic than other.  The HMaster UI would be helpful
> for determining the spread of regions per table across regionservers.
>
> On Mon, Apr 23, 2012 at 9:41 PM, David Charle <[EMAIL PROTECTED]>
> wrote:
>
> > Hi
> >
> > What can make a region server unbalanced when it comes to space ? (and
> > possibly requests too).
> >
> > For example; I have 5 node cluster (replication factor of 3); and in
> which
> > all 4 has same size; where as one node is almost double in size for
> /hbase.
> >
> > Any help will be appreciated; esp what makes the skew and how to fix it ?
> >
> > Thanks
> > David
> >
>