What is wrong with this grouped disk ops query

collectd
grafana
influxdb
#1

I have seen some examples of disk io charts like this one.

But I wonder if these are correct, if I compare my ‘grouped’ chart with individual data than the grouped one is just of one disk. (sdg here in the example)

One disk
SELECT non_negative_derivative(last(“value”), 10s) FROM “disk_read” WHERE (“type” = ‘disk_ops’ AND “host” = ‘c01’ AND “instance” = ‘sdb’) AND timeFilter GROUP BY time(__interval) fill(null)

All disks
SELECT non_negative_derivative(last(“value”), 10s) FROM “disk_read” WHERE (“type” = ‘disk_ops’ AND “host” = ‘c01’) AND timeFilter GROUP BY time(__interval), “host” fill(null)

#2

Hi,

Yes that example is from my side.
In fact what I’ve presented is correct and ok, you can try using my example.
Depends on what you want to achieve?

Kind Regards,