Hi, We have a production cluster homogeneous in terms of HDD devices and I'm a little bit surprised that the osd_mclock_capacity_iops_hdd computed for each OSD is so different (basically a x2 between the lowest and highest values). I understand that sometimes the OSD bench is perturbated by external factors leading to an inappropriate value and if it is too low, it may impact in particular deep scrub duration. The documentation [1] explains that the OSD bench is run at OSD initialization, which is, I guess, startup time. It also suggests that it can be run manually but I guess it makes no sense if the OSD is up because of the concurrent activity. Am I right? How is the bench command supposed to be run as I guess it doesn't work if the OSD is not up? Also, the documentation explains that you can define a value that you measured and seems to suggest that once defined, it will not be updated. Am I right? If yes, does it mean that once the automatic bench has determined a value the only way to update it is to delete it from the config and restart the OSD (if you want the automatic bench to update/redefine it)? Best regards, Michel [1] https://docs.ceph.com/en/squid/rados/configuration/mclock-config-ref/