nodetool setcachekeystosave 

Sets the number of keys saved by each cache for faster post-restart warmup.

Sets the number of keys saved by each cache for faster post-restart warmup.

Synopsis 

$ nodetool <options> setcachekeystosave -- <key-cache-keys-to-save> <row-cache-keys-to-save>
Options
Short Long Description
-h --host Hostname or IP address
-p --port Port number
-pwf --password-file Password file path
-pw --password Password
-u --username User name
-- Separates an option from an argument that could be mistaken for a option.
Other options are:
  • key-cache-keys-to-save is the number of keys from the key cache to save to the saved caches directory.
  • row-cache-keys-to-save is the number of keys from the row cache to save to the saved caches directory.

Description 

This command saves the specified number of key and row caches to the saved caches directory, which you specify in the cassandra.yaml. The key-cache-keys-to-save argument corresponds to the key_cache_keys_to_save in the cassandra.yaml, which is disabled by default, meaning all keys will be saved. The row-cache-keys-to-save argument corresponds to the row_cache_keys_to_save in the cassandra.yaml, which is disabled by default.

The location of the cassandra.yaml file depends on the type of installation:
Package installations /etc/cassandra/cassandra.yaml
Tarball installations install_location/resources/cassandra/conf/cassandra.yaml