Read latency stats in cassandra

Question

What is the difference between read latency and local read latency in tablestats. In my 2-node cluster,while the local read latency are almost cat par,there is significant variance in 'read latency'.What does that indicate and what may cause this?

Answer 1

"Local read latency" is for specific table. The "Read Latency" is for keyspace it's aggregate of latencies for all tables in the given keyspace (but may depend on version - see CASSANDRA-11226)

In your case you need to check all tables in given keyspace to find what table may influence the aggregate.