[jasonhansel]

It'd be interesting to see an RDBMS that actually dynamically measures the performance characteristics of the drive it's running on (by occasionally running small "fio"-like benchmarks, or by inferring them from scan execution times).

[touisteur]

Genuinely curious: where would one expect the drive performance to fluctuate? Wear ? Lack of TRIM ? Some form of timely GC process on disk firmware ? Fragmentation or compaction of some sort ? Maybe weird shenanigans with RAID setups with disks from different vendors and batches ?

Embarking right now on a long-term embedded storage project and wondering what people actually monitor (apart from SMART and latency/throughput at app or db-level).

[magicalhippo]

A lot of databases are served over SAN, where the underlying performance can depend on contestion, as well as less frequent events such as faulty or new hardware.

[touisteur]

Oh thanks. Forgot about this case.

[nine_k]

It could be regular, like SQL "analyze table", it could be one-off. The point is that it would be an automatic tool.

[touisteur]

I'm not harping on the usefulness. More like trying to understand what would be the merit or use-case of frequent or permanent monitoring of this. Are there know failure/degradation modes from the storage HW or the filesystem, or database problems that would be detected by running this continuously. Sibling answer talks about SAN, which makes sense. Wondering what the other use-cases are here.

Otherwise, yes, of course,using it as calibration after any HW change would be interesting.