# Nodetool cfhistograms¶

cfhistograms <keyspace> <cfname>- This command provides statistics about a table, including number of SSTables, read/write latency, partition size and column count. cfhistograms covers all operations since the last time you ran the nodetool cfhistograms command. This command uses the following syntax:

nodetool cfhistograms keyspaces cfname


For example: to get statistics about the standard1 table in the keyspaces1 keyspace, use this command:

nodetool cfhistograms keyspaces1 standard1

Percentile SSTables value Write Latency Read Latency Partition Size Cell Count
50% 10.00 42.00 20.00 210 5
75% 20.00 42.00 24.00 280 5
95% 25.00 42.00 42.00 300 5
98% 25.00 42.00 770.00 310 5
99% 26.00 42.00 2759.00 310 5
Min 00.00 36.00 7.00 210 5
Max 26.00 42.00 35425.00 310 5

In this example, 95% of the write latency measurements were 42 microseconds (μs) or less, 95% of the read latencies were 42 μs or less, and 95% of the partitions are 300 bytes or less. The SSTables column means that the 95% read request refers to 25 SSTables.

Parameter Description
SSTables Distribution number of sstable per read
Write Latency Distribution of the Write Latency