Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
HBase >> mail # dev >> HBase balancer policy issue


Copy link to this message
-
Re: HBase balancer policy issue
When doing balance, Can we take into account the compaction status of
regions.
Currently, even the region is doing compaction, it can also be interrupted
to response to reassign.
On Sun, May 29, 2011 at 12:57 AM, Schubert Zhang <[EMAIL PROTECTED]> wrote:

> Thanks, I think it is HBASE-3373
>
> On Fri, May 20, 2011 at 11:33 PM, Ted Yu <[EMAIL PROTECTED]> wrote:
>
> > I think your request is described in
> > https://issues.apache.org/jira/browse/HBASE-3373
> >
> > Practically speaking, the scenario below can hardly occur (in trunk, at
> > least).
> > If the tables are created with pre-split regions, the regions would be
> > round-robin distributed.
> > If the tables are created with single region, subsequent write operations
> > would cause the region split. Balancer would offload young regions to
> other
> > servers - see HBASE-3609
> > <https://issues.apache.org/jira/browse/HBASE-3609>which is not in 0.90
> > branch.
> >
> > Refer to
> > http://zhihongyu.blogspot.com/2011/04/load-balancer-in-hbase-090.htmlfor
> > details.
> >
> > Cheers
> >
> > On Fri, May 20, 2011 at 12:25 AM, Schubert Zhang <[EMAIL PROTECTED]>
> > wrote:
> >
> > > I have a question about HBase balancer.
> > >
> > > In release 0.90.x, it seems the balancer only regards the number of
> > regions
> > > and balance these regions into every regionserver.
> > >
> > > If we have two tables (A and B) now, each have 100 regions.
> > > Then, a extreme situation is:
> > >
> > > RegionsServer1: 100 regions, which all belong to table A
> > > RegionsServer2: 100 regions, which all belong to table B
> > >
> > > If my application access table B heavy, the almost all opetations hit
> > > RegionsServer2, it is not balance.
> > >
> > > I have a idea about the balance policy:
> > > (1) Firstly balance for each table
> > > (2) Then, overall balance.
> > >
> > >
> > > Schubert
> > >
> >
>

--
Best Regards
Anty Rao