I found that the dashboard does not provide the equivalent of avio from atop, or lat metric from fio, which is an average time for execution for IO request.
Basically, it's a reverse of IOPS for the case when there is a single-threaded (iodepth=1) load. For multiqueue case it's more complicated, but this metrics shows the execution time for IO request.
I played a bit with dashboards and prom, run some fio benchmarks under prom scraping to verify results, and my current formula looks like this:
I found that the dashboard does not provide the equivalent of
avio
from atop, orlat
metric from fio, which is an average time for execution for IO request.Basically, it's a reverse of IOPS for the case when there is a single-threaded (iodepth=1) load. For multiqueue case it's more complicated, but this metrics shows the execution time for IO request.
I played a bit with dashboards and prom, run some fio benchmarks under prom scraping to verify results, and my current formula looks like this:
(io_time_rate / (write_requests + read_requests).
I checked it with synthetic load iodepth=1, iodepth=4 and 32, they all are consistent with fio and atop output.
Should I add one more graph? Is this formula sounds right?