IO500

What It Is

IO500 is a benchmark suite used to evaluate HPC storage across both bandwidth-heavy and metadata-heavy workloads. It combines tools such as IOR and mdtest into a standard run and scoring model.

Why It Matters for MASS

• Broader coverage than a single IOR run
• Visibility into both data-path and metadata behavior
• Useful for acceptance testing, comparison runs, and repeatable regression checks

How To Use with MASS

1. Prepare one or more Linux clients with full MASS client packages and mount the target MASS volume on every client that will participate in the run.
2. Obtain the upstream IO500 source tree and build its benchmark toolchain according to the upstream instructions.
3. Configure the suite so that its data directories and result directories live on the MASS mount point.
4. Point the suite at the MPI launcher and host list for the clients that can reach the MASS storage network.
5. Start with a debug or shortened configuration to verify path layout, permissions, and node-to-node launch behavior before running a full benchmark.
6. Run the full configuration only after the smaller validation run succeeds.

Notes

• Official IO500 submission results must use the upstream suite and its rules; do not substitute the bundled boostx-ior binary for scored runs.
• Make sure every participant sees equivalent filesystem paths and permissions for the MASS target directories.
• Record the MASS client version, mount options, and client topology alongside the results so later comparisons stay meaningful.