The tools, rados bench, and RADOS load-gen, which we discussed in the last recipe, are used to benchmark the Ceph cluster pool. In this recipe, we will focus on benchmarking the Ceph Block Device with the rbd bench-write tool. The ceph rbd command-line interface provides an option known as bench-write, which is a tool to perform write benchmarking operations on the Ceph Rados Block Device.