Increasing region server handler count

Region server keeps a number of running threads to answer incoming requests to user tables. To prevent region server running out of memory, this number is set to very low by default. For many situations, especially when you have lots of concurrent clients, you will need to increase this number to handle more requests.

We will describe how to tune the region server handler count in this recipe.

Getting ready

Log in to the master node as the user who starts HBase.

How to do it...

The following steps need to be followed to increase region server handler count:

1. 1. On the master node, add the following to your hbase-site.xml file:

   hadoop@master1$ vi $HBASE_HOME/conf/hbase-site.xml
   <property>
   <name>hbase.regionserver.handler.count</name>
   <value>40</value>
   </property>
   

2. 2. Sync the changes across the cluster:

   hadoop@master1$ for slave in `cat $HBASE_HOME/conf/regionservers`
   do
   rsync -avz $HBASE_HOME/conf/ $slave:$HBASE_HOME/conf...