>I haven't found any asynchronous IOPS numbers on HDDS anywhere. The internet IOPs are just 1000ms/seek time with a 8ms seek time for moving from the outer to the inner track, which is only really relevant for the synchronous file IO case.

>For asynchronous IO you can just do inward/outward passes to amortize the seek time over multiple files.

Here's a random blog post that has benchmarks for a 2015 HDD:

https://davemateer.com/2020/04/19/Disk-performance-CrystalDi...

It shows 1.5MB/s for random 4K performance with high queue depth, which works out to just under 400 IOPS. 1 queue depth (so synchronous) performance is around a third.