How do I discover consistency level performance?
Before changing the consistency level on read and write operations, discover how your CQL commands are performing using the
TRACING command in CQL.
cqlsh, you can vary the consistency level and trace read and write operations.
The tracing output includes latency times for the operations.
The CQL documentation includes an example comparing consistency levels.
For more information on tracing data, see this post on the DataStax Support Blog, which explains in detail how to locate data on disk.