Performance Monitor counters to analyze network bottleneck

Object Counter Description Expected Value
Network Interface (Network card) Bytes Total/sec Rate at which bytes are transferred on the network adapter. Compare this value with that reported by the Network Interface\Current Bandwidth performance counter, which reflects each adapter’s bandwidth. Average value < 50% of NIC capacity
Network Segment % Net Utilization Percentage of network bandwidth in use on a network segment Average value < 80% of network bandwidth

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