The 3548 is a strange bird.At introduction this switch does not support IPv6. This is Cisco custom switch on a chip silicon. It has 3 pools of buffers that support 16 ports each. So 1/3 of the total RAM (5 MB) is available to an output port.
Cisco has a nice architecture review that includes this figure and explains what they are doing. The Nexus 3548 includes the ability to do fine grained reporting on packet buffer utilization. The reports are similar to Arista LANZ.
The Lippis Report published a commissioned review Cisco Nexus 3548 Top-of-Rack Switch Performance and Power Test with a cover date of July, 2013. Registration is required to get a copy of the report. Like many Lippis reviews they conclude:
The Cisco Nexus 3548 represents a new breed of data center ToR switches. . .
They use those words a lot. Lippis does not cover microburst capability or packet buffering. These are covered in the architecture paper.
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A deep dive on buffer monitoring was presented at CiscoLive! in July 2016. Here, in each one-second interval buffer occupancy was measured 250 times and the count of hits on each bucket are reported. In this example, a slug of traffic loads the buffers which then drain over several seconds. Note bene, the oldest reports are at the bottom and time increases toward the top of the display.
Slide 28 from BRKDCN-3020 Nexus3548# show hardware profile buffer monitor interface ethernet 1/4 detail Detail CLI issued at: 09/10/2015 22:15:42 KBytes 384 768 1152 1536 1920 2304 2688 3072 3456 3840 ... 6144 us @ 10Gbps 307 614 921 1228 1535 1842 2149 2456 2763 3070 ---------------------------------------------------------------- 09/10/2015 22:15:41 0 0 0 0 0 0 0 0 0 0 09/10/2015 22:15:40 0 0 0 0 0 0 0 0 0 0 09/10/2015 22:15:39 0 0 0 0 0 0 0 0 0 0 09/10/2015 22:15:38 0 0 0 0 0 0 0 0 0 0 09/10/2015 22:15:37 34 0 0 0 0 0 0 0 0 0 09/10/2015 22:15:36 139 111 0 0 0 0 0 0 0 0 09/10/2015 22:15:35 0 67 179 4 0 0 0 0 0 0 09/10/2015 22:15:34 0 0 0 174 76 0 0 0 0 0 09/10/2015 22:15:33 0 0 0 0 102 148 0 0 0 0 09/10/2015 22:15:32 0 0 0 0 0 30 178 43 0 0 09/10/2015 22:15:31 0 0 1 0 0 1 0 208 0 0 09/10/2015 22:15:30 0 0 0 0 0 0 0 0 0 0 ====================================================================Ivan Pepeinjak commented on the Nexus 3548 in a blog post comparing it directly with the Arista 7150S.
Cisco has rolled the silicon in the 3548 and produced a new model March 2015. Quoting:
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The Cisco Nexus 3548x and 3524x Switches (Figure 4) are the next generation of the Cisco Nexus 3500 platform. Like the previous generation, these switches are compact 1RU form-factor 10 Gigabit Ethernet switches and provide line-rate Layer 2 and 3 switching with ultra-low latency. In addition, they consume 25% less power. This new generation introduces powerful hardware-based multicast NAT and latency monitoring capabilities and a second USB port for easier manageability.