Enabling and configuring caching 

Using CQL to enable or disable caching.

Use CQL to enable or disable caching by configuring the caching table property. Set parameters in the cassandra.yaml file to configure global caching properties:

Configuring the row_cache_size_in_mb (in the cassandra.yaml configuration file) determines how much space in memory Cassandra allocates to store rows from the most frequently read partitions of the table.

The location of the cassandra.yaml file depends on the type of installation:
DataStax Enterprise 5.0 Installer-Services and package installations /etc/dse/cassandra/cassandra.yaml
DataStax Enterprise 5.0 Installer-No Services and tarball installations install_location/resources/cassandra/conf/cassandra.yaml
Cassandra package installations /etc/cassandra/cassandra.yaml
Cassandra tarball installations install_location/resources/cassandra/conf/cassandra.yaml

Procedure

Set the table caching property that configures the partition key cache and the row cache.
CREATE TABLE users (
  userid text PRIMARY KEY,
  first_name text,
  last_name text,
)
WITH caching = { 'keys' : 'NONE', 'rows_per_partition' : '120' };