HBase - number of regionserver used

[Andrea <an...@gmail.com>]

Hi, I have HBase above Hadoop with one master node, one zookeeper node and 
four regionservers. When I turn up everything, on two nodes (or sometime the 
same node) are created the tables .META. and -ROOT- and then I create a table 
called 'usertable' which goes to another random node.

Now, when i test the system (with YCSB tool), i notice that only the 
regionserver which contain the table 'usertable' works and split the region. 
So it means that only one node works? There's no way to split the load work 
on the other nodes?

And further more, when i try to load a lot of rows, it crashes and I am not 
able to restore my table, and I have to rebuilt the entire system from zero.

Thank you in advance for your time!

Re: HBase - number of regionserver used

[Vinay Kashyap <vi...@gmail.com>]

Andrea

Looks like you might have to consider creating the table using pre splits..
In order to split the load to all the region servers, you have to decide
the key splits and use the splits while creating the table. You can use
hbase shell command to specify the splits.

Pre split regions shows very good performance for hbase load with YCSB..

Thanks and regards
Vinay Kashyap
On Nov 12, 2013 2:20 AM, "Andrea" <an...@gmail.com> wrote:

> Hi, I have HBase above Hadoop with one master node, one zookeeper node and
> four regionservers. When I turn up everything, on two nodes (or sometime
> the
> same node) are created the tables .META. and -ROOT- and then I create a
> table
> called 'usertable' which goes to another random node.
>
> Now, when i test the system (with YCSB tool), i notice that only the
> regionserver which contain the table 'usertable' works and split the
> region.
> So it means that only one node works? There's no way to split the load work
> on the other nodes?
>
> And further more, when i try to load a lot of rows, it crashes and I am not
> able to restore my table, and I have to rebuilt the entire system from
> zero.
>
> Thank you in advance for your time!
>
>

Re: HBase - number of regionserver used

[Jia Wang <ra...@appannie.com>]

Hi Andrea

Which version of HBase are u using? I assume you are using HBase 0.94, the
default split policy is IncreasingToUpperBoundRegionSplitPolicy, which will
split the region when it reachs 512M, 1152M,.. So initially you have one
region that's correct, once you get two regions or more, the load balance
process will run every 5 minutes to reassign you region to different of
your region servers, you should wait for them to take effect.

I'm interesting in what error message you got when the region server crash?

Cheers
Ramon


On Tue, Nov 19, 2013 at 3:01 AM, Asaf Mesika <as...@gmail.com> wrote:

> The crashing sounds odd. What's your exception?
>
> On Monday, November 11, 2013, Andrea wrote:
>
> > Hi, I have HBase above Hadoop with one master node, one zookeeper node
> and
> > four regionservers. When I turn up everything, on two nodes (or sometime
> > the
> > same node) are created the tables .META. and -ROOT- and then I create a
> > table
> > called 'usertable' which goes to another random node.
> >
> > Now, when i test the system (with YCSB tool), i notice that only the
> > regionserver which contain the table 'usertable' works and split the
> > region.
> > So it means that only one node works? There's no way to split the load
> work
> > on the other nodes?
> >
> > And further more, when i try to load a lot of rows, it crashes and I am
> not
> > able to restore my table, and I have to rebuilt the entire system from
> > zero.
> >
> > Thank you in advance for your time!
> >
> >
>

Re: HBase - number of regionserver used

[Asaf Mesika <as...@gmail.com>]

The crashing sounds odd. What's your exception?

On Monday, November 11, 2013, Andrea wrote:

> Hi, I have HBase above Hadoop with one master node, one zookeeper node and
> four regionservers. When I turn up everything, on two nodes (or sometime
> the
> same node) are created the tables .META. and -ROOT- and then I create a
> table
> called 'usertable' which goes to another random node.
>
> Now, when i test the system (with YCSB tool), i notice that only the
> regionserver which contain the table 'usertable' works and split the
> region.
> So it means that only one node works? There's no way to split the load work
> on the other nodes?
>
> And further more, when i try to load a lot of rows, it crashes and I am not
> able to restore my table, and I have to rebuilt the entire system from
> zero.
>
> Thank you in advance for your time!
>
>