randstream: Reproducible Stream Generator and Validator

randstream is a high-performance command-line utility for creating and validating reproducible, pseudo-random data streams. It is designed for use cases such as verifying storage integrity, benchmarking I/O performance, or generating large, arbitrary datasets for testing.

The utility uses a seed to ensure that the generated data is reproducible. In order to be validatable without regeneration on the data, the stream includes a checksum of 4 bytes at the end of each chunk. It also uses parallel processing to ensure maximum throughput on modern hardware, while keeping the output identical independently of the number of parallel tasks.

Installation

cargo install randstream

Usage

randstream has two main commands: generate and validate.

Generating a Random Stream (generate)

Use the generate command to create a reproducible stream of pseudo-random data.

Validating a Random Stream (validate)

Use the validate command to verify that an existing stream has not been corrupted or altered. The validation process will re-generate the data internally using the same seed and compare it byte-for-byte with the input stream.

Examples

Fill a whole block device:

randstream generate /dev/xvdb

Generate a 100 GB file using a specific seed and 2 parallel tasks:

randstream generate --size 10G --seed 1a234e5678 --jobs 2 output.bin

Validate a previously generated stream:

randstream generate output.bin