# Brocade Management Software Community

## How Switch Port utilization is calculated in BNA?

• #### 1.  How Switch Port utilization is calculated in BNA?

Posted 08-20-2018 09:30 AM

Is there any mathematical formula which can explain the logic behind calculating the BNA Switch Port utilization? I would like to confirm if BNA is reporting correct values.

Because the port traffic is very less whereas utilization is showing 100%. How can the utilization is 100% when the port traffic is less?

• #### 2.  What is calculation or formula for port throughput%28Transfer Rate%29 and Port utilization with example

Posted 08-20-2018 11:32 PM

Hi All,

How port throughput and utilization is calculated (formula). Please provide us the example for FC switch port.

Regards,

Dnyaneshwar

• #### 3.  Re: What is calculation or formula for port throughput%28Transfer Rate%29 and Port utilization with example

Posted 08-21-2018 12:04 AM

@Dnyaneshwar

I moved the thread to Fibre Channel Forum, and notice is another threads with the same/ similarly question posted yesterday.

are you the same user ?

• #### 4.  Re: What is calculation or formula for port throughput%28Transfer Rate%29 and Port utilization with example

Posted 08-22-2018 03:25 AM

Hi Antonio,

Thanks for taking forward this request. Yes, we are from the same organization.

Let me provide some more details for this request.

For Port Tx/Rx percent utilization, we have observed formula in "Brocade Monitoring and Alerting Policy Suite Configuration Guide, 8.1.0" on page no. 37 as (traffic/port speed)*100.

But when we have done actual calculations then calculated value comes somewhat different.

Tx = 204.317 Mb/s
Port Speed = 8 Gb/s

After calculation Tx Utilization(%) = 2.55

But on BNA server Tx Utilization(%) has observed as 24.04

Is there any other formula has been used for calculation? If yes, Could you please provide it to us.

Thanks & Regards,

Bhushan Patil

• #### 5.  Re: What is calculation or formula for port throughput%28Transfer Rate%29 and Port utilization with example

Posted 09-19-2018 01:01 AM

Hi,

Are you sure that TX trafic you picked up is in Mb (bits) and not in MB (bytes) ?

BNA (performance graph ) or portperfshow command diplay value in MB/s.

If it was MB/s, the result of your calculation would be close from what BNA Tx utilization was displaying.

Calculation : [ (8*0.204317) / 8 ] / 100 = 20.4317 %

BNA server Tx Utilization(%) has observed as 24.04

Regards,

jms.

• #### 6.  Is there any mathematical formula which can explain the logic behind calculating the BNA Switch Port

Posted 08-26-2018 07:48 AM

Is there any mathematical formula kissanime which can explain the logic groupme behind calculating the BNA Switch Port utilization? I would like to confirm if BNA is reporting correct values. Because the port traffic is very less whereas letgo utilization is showing 100%. How can the utilization is 100% when the port traffic is less?

• #### 7.  Re: Is there any mathematical formula which can explain the logic behind calculating the BNA Switch Port

Posted 09-03-2018 09:24 AM

Shane,

Kindly let me know if you happen to know the calculation of port utilization in BNA.