In this section, we'll explore what to do about it. The larger a cluster's OSD count grows, the wider the variance can become, approximating a bell curve. The ceph osd df utility can be used to summarize the utilization of each OSD along with an indication of how much it varies from the overall average. Here's an example of a cluster's distribution before and after we take action. Here our least full OSD is 29% full, just 80% of the cluster's mean, and the most full is over 44% full, 124% of the cluster's mean.
# ceph status
cluster ce2bcf60-efd0-1138-bxc5-936beak1s9a7
health HEALTH_OK
monmap e1: 5 mons at {mon01=10.7.4.4:6789/0,mon02=10.7.4.5:6789/0,mon03=10.7.4.132:6789/0,mon04=10.7.4.133:6789/0,mon05=10.7.5.4:6789/0}
election ...
