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How is the metric calculated (P95)

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Article ID: 254053

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Updated On:

Products

DX NetOps

Issue/Introduction

Please see image.  I thought Utilization - 95 Percentile was supposed to show the avg of Utilization IN - 95 Percentile Utilization OUT - 95 Percentile 
My image shows:

Utilization - 95 Percentile 71.2%
Utilization - IN 95 Percentile 44.59%
Utilization - OUT 95 Percentile 51.39%

Where is 71.2% being calculated from?

Environment

Release : 21.2

Cause

Utilization metric itself is the higher of In OR Out values.  So it will then take the 95% of the Utilization value.
The 95% for In OR Out is based ONLY on the In OR Out values.   So if the utilization switches between in and out over the course of the time range, you are probably gonna end up with a 95% > IN OR OUT 95%

If the IN always is the highest Util value, then IN 95% should match Util 95%.  Same if OUT Util value was highest the entire time range, then OUT 95% would match Util 95%

For full duplex, the High Speed Iinterface Vendor Cert uses higher of IN or OUT;
half duplex is In+Out

You might want to do a trend graph (hourly) of In/Out/Util for the same time range.  See if In or Out swap positions during the time range.

The highlighted interface must have had a lot of swapping back and forth between IN/OUT.

Resolution

Functioning as designed