Hi, I am running Cassandra 0.7.4 and I monitor the nodes using JConsole.
I am trying to figure out the location Cassandra read the returned rows and there are few strange things... 1. I am reading few rows (using Hector) and the org.apache.cassandra.db.ColumnFamilies.<my-keyspace>.<my-cf>.ReadCount remains 0 - It remains 0 with MEMTable and after flushing the MEMTable. 2. The column family is configured to run with row-cache and key-cache and although I am reading the same row over and over the row-cache size/requests remains 0. The key-cache size/requests attributes are changed. Why Cassandra does not cache a row that was requested few times? What the ReadCount attribute in ColumnFamilies indicates and why it remains zero. How can I know from where Cassandra read a row (from MEMTable,RowCache or SSTable)? does the following correct? In read operation Cassandra looks for the row in the MEMTable - if not found it looks in the row-cache - if not found it looks in SSTable (after looking in the key-cache to optimize the access to the SSTable)? 10x
