The document discusses performance testing of HBase using YCSB (Yahoo! Cloud Serving Benchmark). It details steps taken to build and configure YCSB to work with HBase on a CDH cluster, load 50 million records into an HBase table, and run YCSB workload tests in modes A-K with threading from 1 to 128. Graphs show results for throughput, latency for each workload and threading configuration. The HBase environment consisted of 3 region servers and 10 data nodes on CentOS 6.5 servers with a total of 990GB memory and 24 CPU cores across servers.