Type 'help' or '?' for help. Type 'quit' or 'exit' to quit. cassandra> connect cass01/9160 cassandra> get TimeFrameClicks.Standard2['test_cassandra_alive'] Exception null
The data exists and I can grab the data after I restart all the nodes, but once the cluster runs for a few minutes I cannot grab this specific key or random other keys. It takes about 3 seconds until the Exception null message. My storage-conf.xml is very simple: <Keyspace Name="TimeFrameClicks"> <ColumnFamily Name="Standard2" CompareWith="UTF8Type" /> .... Now my data is very small like 20 GB across 4 servers. Writes consistently remain fast, yet reads fail like crazy. I hope its something that I am doing wrong because nodetool cfstats says that the read latency for the keyspace and this specific column family is less then 0.3 ms which means that something is lying to me. To head off some questions: CPU utilization is very little. There is hardly any I/O on the box The servers are all the same class enterprise boxes There is 12 GB of ram per server Each Server uses a local RAID. Nothing in any of the system logs that indicates there any problem. Additionally is there a stat or series of stats that I can lookup to determine the health of read performance.
