Does increasing replication factor on a cluster also increase the read speed?
I understand that when replication factor is 1, and there’s 6 nodes and the tokens are distributed equally – then it’s only 16,66% chance that given node has the data, if it does not have it, it asks the node responsible and that takes extra time.
I guess that with replication factor set to 6, each node has the full dataset and can fetch data immediately without asking other nodes (we’re using read consistency=1). So increasing replication factor should increase reading speed. Is this correct?
Our app has relatively few writes but more than 10k get() operations per second. We have 6 nodes in the cluster and we need all read operations to be extremely fast, that’s why we’re looking for a way to improve cassandra’s read performance.
That’s correct, as long as you’re using ConsistencyLevel.ONE.