sflow polling rate

[NSB]

Hi,

What is the impact of increasing/decreasing the polling rate in sflow?

shawoo

[Peter Phaal]

On Friday, December 16, 2016 at 7:28:51 AM UTC-8, NSB wrote:

Hi,

What is the impact of increasing/decreasing the polling rate in sflow?

sFlow-RT updates counter based metric values whenever it receives a new set of sFlow counters. For example, if you set the sFlow agent polling interval to 30 seconds, then the counter based metrics will update every 30 seconds (and represent a 30 second average). Polling intervals of less than 10 seconds should be avoided since they tend to result in noisy measurements because of variability between the time the counter was read from hardware and the time it is exported by the sFlow agent. Longer polling intervals generate more accurate results.

sFlow-RT flow based metrics are updated whenever a new packet sample is received and have a faster response than counter based metrics:

http://blog.sflow.com/2013/02/measurement-delay-counters-vs-packet.html 

The following article discusses sampling and polling settings and provides some suggested default values:

http://blog.sflow.com/2013/06/large-flow-detection.html