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• Xms1024m -Xmx1024m -XX:MaxPermSize=512m

• Change the /etc/security/limits.conf with the following values:

  Code Block
  * soft nofile 4096 * hard nofile 65535

• Recommended OS: Linux
• At least 10 GB storage capacity in each node
• At least 100 Mbps network bandwidth
• Set hadoop.root.logger=ERROR

• Have separate disks for your commit log and data dirs (sstables)

• Set the Heap memory as follows:

  System memory	Heap size
  Less than 2 GB	1/2 of system memory
  2-4 GB	1 GB
  More than 4 GB	1/4 system memory, but not more than 8GB

• Set following configuration in cassandra.yaml according to your hardware resources:

  • concurrent_reads: 4 * no of cores
  • concurrent_writes: 8 * no of CPU cores

Also see http://www.datastax.com/docs/1.0/operations/tuning in Cassandra documentation.

In order to increase the memory size of Hive , increase try the following configurations:

• Increase the setting for the Hadoop heapsize. For example increase it to 4096 as shown below:
  export HADOOP_HEAPSIZE=4096
• Add the below entry in the <BAM_HOME>/repository/conf/advanced/hive-site.xml file

• :  

<property>  
   <name>mapred.child.java.opts</name>  
  export HADOOP_HEAPSIZE=4096 
   <value> -server -Xmx512M</value>  
 </property>