I am looking at the utilization on a Catalyst 3560-E. I am running a test with eight 1 GIGE links RXing at 95 % utilization. All of the traffic is going to a TenGigE port. The device on the TenGigE port is echoing back all of the traffic received, so the 1 GIG links are TXing at 95% as well.
When I do a "show controllers utilization", the port utilization numbers are correct, but the fabric utilization is higher than I would expect. The fabric should be 128 gigbits / second in this switch, and there is 7.6 gigabits TX/RX to the ten gig port. The fabric utilization is at 49%. I would expect 7.6 / 128 = 5.9% or possible double that. Am I doing the utilization calculation incorrect?
Switch#show controllers utilization
Port Receive Utilization Transmit Utilization
Gi0/1 0 0
Gi0/2 0 0
Gi0/3 0 0
Gi0/4 0 0
Gi0/5 0 0
Gi0/6 0 0
Gi0/7 0 0
Gi0/8 0 0
Gi0/9 95 95
Gi0/10 0 0
Gi0/11 95 95
Gi0/12 95 95
Gi0/13 0 0
Gi0/14 0 0
Gi0/15 0 0
Gi0/16 0 0
Gi0/17 0 0
Gi0/18 0 0
Gi0/19 95 95
Gi0/20 0 0
Gi0/21 95 95
Gi0/22 95 95
Gi0/23 95 95
Gi0/24 95 95
Gi0/25 0 0
Gi0/26 0 0
Gi0/27 0 0
Gi0/28 0 0
Te0/1 76 76
Te0/2 0 0
Total Ports : 30
Switch Receive Bandwidth Percentage Utilization : 49
Switch Transmit Bandwidth Percentage Utilization : 49
Switch Fabric Percentage Utilization : 49
