Thanks very much for your replies. Something was unclear in my previous emails. I had one node started first and another was added in later. And there're already some regions created in the first started node. Then I started to import more data into the same table and found that it's always the first node that keeps serving the data writes.
Actually I was expecting that the region data would be re-balanced to another data node. And I did see in the master log that HBase master is trying to unassigning some regions from the overloaded node and re-assign them to the less-loaded node. But the real data was never migrated. I think I observed the region index and cache rebalancing from the master log (correct me if I were wrong). Does anyone know how frequently this happens? Another question is, does HBase support data and I/O rebalancing? Or I should rely on HDFS to do data rebalancing? I guess HBase should also support data rebalancing otherwise every time I restart HBase the regions will have to be rebalanced again. Will someone tell me how to configure or program HBase to do data rebalancing? Thanks, -- Weiwei On Mon, Mar 14, 2011 at 2:43 PM, Ryan Rawson <ryano...@gmail.com> wrote: > What version of HBase are you testing? > > Is it literally 0 vs N assignments? > > On Mon, Mar 14, 2011 at 1:18 PM, Weiwei Xiong <xion...@gmail.com> wrote: > > Thanks! > > > > I checked the master log and found some info like this: > > " timestamp ***, INFO org.apache.hadoop.hbase.master.HMaster: balance > > hri=***, src=***, dst=*** " > > > > So I assume the balancer is running. There's no failing info there, but I > > didn't see the regions were actually balanced as the log states. > > > > Is it possible that I have been keeping dumping data into the table thus > the > > balancing won't work? > > > > Thanks, > > -- Weiwei > > > > On Mon, Mar 14, 2011 at 12:15 PM, Stack <st...@duboce.net> wrote: > > > >> Check the master log. See if the load balancer is running or not. It > >> usually runs every 5 minutes by default. It may not run if regions > >> are transitioning. It'll log regardless. > >> > >> St.Ack > >> > >> On Mon, Mar 14, 2011 at 10:50 AM, Weiwei Xiong <xion...@gmail.com> > wrote: > >> > Hi, > >> > > >> > I recently set up a 2-node Hadoop and HBase cluster and am trying to > load > >> > data into my HBase table using HBase client. > >> > > >> > The issue bothers me is that the data are always written into one node > of > >> > the cluster, i.e., all the regions of the hbase table are on one node. > >> > > >> > Is there any configuration I need to change for make the load > balanced? > >> > > >> > Thanks, > >> > -- w > >> > > >> > > >
