As mentioned in Chapter 1, Understanding the HBase Ecosystem, ZooKeeper provides distributed synchronization and group service to HBase. It is one of the necessities of HBase, and hence, we have to optimize it. Use the following setting for optimization:

<property>
  <name>zookeeper.session.timeout</name>
  <value>3000</value>
</property>

The default value for this setting is 3 minutes. This decides how often master should check for server crashes. We can decrease it so that the server crashes can be noticed quickly, but if this value decreases, we need to take care of GC. In the case of full GC, the server might not respond while running fine, and it might be reported as crashed. This configuration can be overridden in the hbase-site.xml file.

This value should be increased if there is a timeout while writing to the HBase cluster. If it is too small, and while writing huge amounts of data to HBase, GC happens, resulting in the pause...