Thanks for your swift response, Ramkrishna and Anoop. And I will explicate what we are doing now below.
We are trying to explore a systematic way to design the appropriate data schema for various applications in HBase. So we first designed several data schemas for each dataset and evaluate them with the same queries. The queries are designed based on the requirements, such as selecting the data with a matching expression, finding the difference between two snapshots. The queries were processed with user-level Coprocessor. In our experiments, we found that under some data schemas, the queries cannot get any results because of the connection timeout and RS crash sometimes. We observed that in this case, the queried data were centered in a few regions locating in a few region servers. We think the failure might be caused by the excess workload in these few region servers and the inappropriate load balance. To our best knowledge, this case can be avoided and improved by the well-distributed regions across the region servers. Therefore, we have been thinking to add a monitoring and management component between the client and server, which can schedule the queries/jobs from client side and distribute the regions dynamically according to the current workload of each region server, the incoming queries and data locality. Does it make sense? Just my two cents. Any comments? Best Wishes Dan Han On Tue, Sep 25, 2012 at 10:44 PM, Anoop Sam John <[email protected]> wrote: > Hi > Can u share more details pls? What work you are doing within the CPs > > -Anoop- > ________________________________________ > From: Dan Han [[email protected]] > Sent: Wednesday, September 26, 2012 5:55 AM > To: [email protected] > Subject: Distribution of regions to servers > > Hi all, > > I am doing some experiments on HBase with Coprocessor. I found that the > performance > of Coprocessor is impacted much by the distribution of the regions. I am > kind of interested in > going deep into this problem and see if I can do something. > > I only searched out the discussion in the following link. > > http://search-hadoop.com/m/Vjhgj1lqw7Y1/hbase+distribution+region&subj=distribution+of+regions+to+servers > > I am wondering if there is any further discussion or any on-going work? Can > someone point it to me if there is? > Thanks in advance. > > Best Wishes > Dan Han >
