I want to switch from WMI sensors to SNMP for monitoring/recording metrics where a shorter refresh interval is useful for us. Specifically CPU and Network I/O, to start. The currently recommended 60 second interval for WMI does not give us the resolution we need to troubleshoot some issues, so I feel SNMP is the way to go.
I have everything configured and working on our Windows servers with SNMP, however I noticed some strange behaviour in the recorded (historical) data. I have my SNMP sensor refresh interval set to 10 seconds, but it doesn't seem to be receiving updated data from Windows on every scan. For the CPU sensor it seems the values change every 2-3 scans, and for I/O sensor the values every 2-3 scans fall to 0 (even though there is constant network use on the monitored interface).
This can be better described by pictures...
I feel this is more of a Windows SNMP issue than a PRTG one - since I do not see this problem when monitoring non-Windows systems via SNMP, even with a 10 second scanning interval. It seems Windows SNMP counters do not refresh on each request, there must be some other mechanism which does this and I don't know how that can be modified/tweaked. I haven't had any luck finding information about SNMP counter refresh times in Windows, so I thought I would ask here!