Port ultilization for Gigabit (HP5406 and SFlow)

[Juergen Bachsteffel]

Hello!

I configured my switch to send SFlow-packets. Everthing works as expected.

I see peeks between 1000 and 9000 frames/s for a specific Uplink-Port.

 I can't interpret the values.

My  question:

What is a normal frame rate for a 1 Gigabit-Uplink Port?

The  Software (SFlowTrend) shows only a few percent of utilization. Hm, ....

Thanks in advance!

Regards,

        Jürgen

P.S. This thread has been moved from Switches, Hubs, Modems (Legacy ITRC forum) to ProCurve / ProVision-Based. - Hp Forum moderator

[netvis · Accepted solution]

A link utililzation of 1% is not unusual for a Gigabit link, particularly in an office environment. In a data center environment, link utilizations would typically be higher.

You might find the following article helpful, it explains how sFlowTrend can be used to understand network activiity

http://blog.sflow.com/2011/06/five-ws.html

[Richard Brodie_1]

A very crude calculation, ignoring framing and stuff; if you're sending maximum size (but not jumbo) packets:

9000 pps * 1500 (bytes/packet) * 8 (bits/byte) = 108000000, roughly 100 Mbit/s.

So 10% tops, probably much less. Usually vendors quote for minimal size (64 byte) packets, where you get about 14 000 pps on plain old Ethernet, 1.4 million on Gigabit.

[Juergen Bachsteffel]

Ok, thank you for your thoughts! Now I see much clearer.

Maybe, I was a bit to fast with my question. At weekend I had an idea by myself. ;-)

I calculated the other way:

1Gbit  / 8 = 1.25 * 10^8

1.25 * 10^8 / 1500 (max. MTU)  = 83333,33 frames/s

So you may send about 80K Frames/s over a Gigabit wire. 

CU

   Juergen