nodetool tablehistograms 

Provides statistics about a table that could be used to plot a frequency function.

Provides statistics about a table that could be used to plot a frequency function.

Synopsis 

$ nodetool <options> tablehistograms -- <keyspace> <table>
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 Remote JMX agent username.
keyspace Name of keyspace.
table One or more table names, separated by a space.
Note: Either keyspace.table or keyspace table can be used to designate the table.
-- Separates an option from an argument that could be mistaken for a option.

Description 

The nodetool tablehistograms command provides statistics about a table, including read/write latency, partition size, column count, and number of SSTables. The report is incremental, not cumulative. It covers all operations since the last time nodetool tablehistograms was run in the current session. The use of the metrics-core library makes the output more informative and easier to understand.

Example 

For example, to get statistics about the libout table in the libdata keyspace, use this command:

$ %CASSANDRA_HOME%/bin/nodetool tablehistograms libdata libout

Output:

libdata/libout histograms
Percentile  SSTables     Write Latency      Read Latency    Partition Size        Cell Count
                              (micros)          (micros)           (bytes)                  
50%             0.00             39.50             36.00              1597                42
75%             0.00             49.00             55.00              1597                42
95%             0.00             95.00             82.00              8239               258
98%             0.00            126.84            110.42             17084               446
99%             0.00            155.13            123.71             24601               770
Min             0.00              3.00              3.00              1110                36
Max             0.00          50772.00            314.00            126934              3973

The output shows the percentile rank of read and write latency values, the partition size, and the cell count for the table.