Thanks for these thorough responses 😃.

If the data being written is random how do you know what was written? Is it a known pattern? Something calculated given its address space?

For perf randread/write test, why was 4KB chosen?

For endurance do you have access to any hardware metrics to compare the running test? The drives should be self reporting endurance, each vendor may vary slightly in how they express it

What are your methods for testing?