Dell PowerConnect Brocade 300 Fabric OS Administrator's Guide v7.1.0 - Page 375

Chapter Bottleneck Detection 13 In this chapter •Bottleneck detection overview 375 •Supported configurations for bottleneck detection 377 •Credit Loss 379 •Enabling bottleneck detection on a switch 380 •Displaying bottleneck detection configuration details 381 •Setting bottleneck detection alerts 382 •Changing bottleneck detection parameters 384 •Advanced bottleneck detection settings 388 •Excluding a port from bottleneck detection 389 •Displaying bottleneck statistics 391 •Disabling bottleneck detection on a switch 392 Bottleneck detection overview A bottleneck is a port in the fabric where frames cannot get through as fast as they should. In other words, a bottleneck is a port where the offered load is greater than the achieved egress throughput. Bottlenecks can cause undesirable degradation in throughput on various links. When a bottleneck occurs at one place, other points in the fabric can experience bottlenecks as the traffic backs up. The bottleneck detection feature enables you to do the following: • Prevent degradation of throughput in the fabric. The bottleneck detection feature alerts you to the existence and locations of devices that are causing latency. If you receive alerts for one or more F_Ports, use the CLI to check whether these F_Ports have a history of bottlenecks. • Reduce the time it takes to troubleshoot network problems. If you notice one or more applications slowing down, you can determine whether any latency devices are attached to the fabric and where. You can use the CLI to display a history of bottleneck conditions on a port. If the CLI shows above-threshold bottleneck severity, you can narrow the problem down to device latency rather than problems in the fabric. You can use the bottleneck detection feature with other Adaptive Networking features to optimize the performance of your fabric. For example, you can do the following: • If the bottleneck detection feature detects a latency bottleneck, you can use TI zones or QoS SID/DID traffic prioritization to isolate latency device traffic from high priority application traffic. Fabric OS Administrator's Guide 375 53-1002745-02