What's the difference between "disk.device.write.requests.rate" and "disk.device.iops" ?
I would like to get the IOPS value from each instance, so I searched some info about Gnocchi metrics, and I found two metrics: disk.device.read/write.requests.rate
and disk.device.iops
.
According to this https://docs.openstack.org/ceilometer/latest/admin/telemetry-measurements.html (page), disk.device.read/write.requests.rate
means "The number of read/write requests" per second, and disk.device.iops
means "Average disk iops per device".
My question is: what is the main difference between these two metrics? I can't find out which is the most suitable choice for me.