Vdbench

Vdbench is a disk I/O benchmarking tool originally developed by Sun Microsystems and now maintained by Oracle. It generates configurable storage workloads to measure performance of storage arrays, disks, and related devices. The tool supports a range of I/O patterns and configurations, making it a common choice for capacity planning, vendor performance validation, and database or virtualization storage testing.

Workloads are defined in a description file that specifies devices, targets, and operations. Vdbench can mix reads and writes, perform sequential or random access, and vary block sizes, queue depths, and thread counts. It can test local disks as well as remote targets over SAN, NAS, or network file systems, modeling scenarios such as OLTP, streaming, or backups. Output includes IOPS, throughput, latency, and percentile latency.

Vdbench runs on Unix-like systems, including Linux and Solaris, and is distributed as part of Oracle's benchmarking tools. It is a command-line utility that typically requires careful preconditioning and a stable test environment for repeatable results.

Because results depend on hardware, software stack, and configuration, Vdbench is used to compare configurations and track performance trends rather than provide absolute forecasts.