Contributed by Doug Hughes

The following is a list of tools that one can use for benchmarking or measuring the performance of a filesystem/volume. It is by no means complete and any additions are greatly appreciated.

1. iostat: builtin
2. sar: like iostat, builtin
3. vxstat: like iostat, comes with VxVM, provides breakouts on things like read-modify writes, reconstruct writes, etc, and and can work on volume, plex, or subdisk level
4. lmbench: Written by Larry McVoy while at SGI, presented at a Usenix conference in 1996, and now offered by bitmover.com
5. IT Service Vision (formerly SAS/CPE) is a tool for performance measurement.
6. iozone is an old relic from comp.sources.misc days (1994!), but still useful for benchmarking sequential file access of varying file and record sizes. I have some mods that allow increasing the record sizes to much larger default values.
7. Vxbench is available free from Veritas and is a good tool for benchmarking Veritas volumes and filesystems (and even non-veritas volumes and filesystems). Capabilities examples here
8. Proctool is a free, unsupported process tool from Sun that is capable of displaying per-process I/O results (manual configuration). caveat: if you are in a foreign country, you must set LC_ALL=C for it to work.
9. Soliddata hasa product for optimizing Oracle hot-spots. I know of no first hand experiences positive or negative with this product.