Pre-fetch cells from Hbase Pre-fetch is enabled via a parameter in HTableClient.startScan method.Pre-fetch is not done for unique and batch Trafodion operations and all native Hbase table access. Pre-fetch is currently disabled for non-unique UMD Trafodion operations.
startScan method invokes pre-fetch to Hbase in a different thread. When the fetchRows method is called, pre-fetch completes, passes cell info to JNI and invokes pre-fetch if there are more rows to be fetched.
We have observed around 45% reduction in response time to fetch 12 million rows of a sizteen partition table in a node via a single process.