@denis.grilli The problem is not the performance of the scan ... the problem is, that this storage device only consists of block devices (disks) that should go into standby mode when not used ... but I think I've found a code line that checks if other-config for an SR contains auto-scan: false... I think ...
Different use cases: Ceph is better with more hosts (at least 6 or 7 minimum) while XOSTOR is better between 3 to 7/8.
We might have better Ceph support in the future for large clusters.