IOR Benchmark on a free HPC Cluster (t2.micro)

You might consider MDtest. MDtest is an MPI-based application for evaluating the metadata performance of a file system and has been designed to test parallel file systems. MDTest is not a Lustre-specific benchmark and can be run on any POSIX-compliant file system, but it does require a fully installed and configured file system implementation in order to run.

The High Performance Computing Lens Provides Guidance on Storage https://docs.aws.amazon.com/wellarchitected/latest/high-performance-computing-lens/storage.html

For best results, you should consider using an HPC Optimized instance type https://aws.amazon.com/ec2/instance-types/#HPC_Optimized