1. Using Oracle Solaris 11.4 StatsStore and System Web Interface
  2. Performing Operations on Statistic Values
  3. Rate and Delta

Rate and Delta

The op.rate and op.delta operations return the change or rate of change between two consecutive data points of the same resource. For values value1 and value2 recorded at times time1 and time2 , rate and delta are calculated as follows:

  • op.rate is calculated as (value2-value1)/(time2-time1)

  • op.delta is calculated as value2-value1

This result is provided for each pair of consecutive data points.

The following example shows the number of bytes received:

$ sstore export -t 2020-08-26T20:25:28 -e 2020-08-26T20:27:28 -i 40 \
> //:class.link/phys//:res.name/net0//:stat.in-bytes
TIME                VALUE IDENTIFIER
2020-08-26T20:25:28 2198658462.0 //:class.link/phys//:res.name/net0//:stat.in-bytes
2020-08-26T20:26:08 2198754940.0 //:class.link/phys//:res.name/net0//:stat.in-bytes
2020-08-26T20:26:48 2198837272.0 //:class.link/phys//:res.name/net0//:stat.in-bytes
2020-08-26T20:27:28 2198957430.0 //:class.link/phys//:res.name/net0//:stat.in-bytes

The following example shows the difference between each pair of values taken 40 seconds apart:

$ sstore export -t 2020-08-26T20:25:28 -e 2020-08-26T20:27:28 -i 40 \
> //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.delta
TIME                VALUE IDENTIFIER
2020-08-26T20:25:28 96478.0 //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.delta
2020-08-26T20:26:08 82332.0 //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.delta
2020-08-26T20:26:48 120158.0 //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.delta

The following example shows the difference between each pair of values divided by the difference between time stamps for those values (40):

$ sstore export -t 2020-08-26T20:25:28 -e 2020-08-26T20:27:28 -i 40 \
> //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.rate
TIME                VALUE IDENTIFIER
2020-08-26T20:25:28 2411.95 //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.rate
2020-08-26T20:26:08 2058.3 //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.rate
2020-08-26T20:26:48 3003.95 //:class.link/phys//:res.name/net0//:stat.in-bytes//:op.rate

Delta and rate are not necessarily exactly the same when the time difference is one second because the actual time the data was posted in the statistics store is not necessarily exactly at the reported second.