Ceph has opt-in telemetry since a couple of years. This dashboard[0] panel suggests there are about 4-5 clusters (that send telemetry) within the 32-64 PiB range.

It would be really interesting to see larger clusters join in on their telemetry as well.

[0] https://telemetry-public.ceph.com/d/ZFYuv1qWz/telemetry?orgI...

That was interesting, thank you. Other folks may also enjoy its sibling dashboard showing the used capacity https://telemetry-public.ceph.com/d/ZFYuv1qWz/telemetry?orgI...