Chapter 7 - 9. Congestion Management in Ethernet Storage Networks以太网存储网络的拥塞管理

Storage I/O Performance Monitoring

Traffic in a storage network is the direct result of an application initiating a read or write I/O operation. Because of this reason, network traffic patterns can be better understood by analyzing the application I/O profile, such as the timing, size, type, and rate of I/O operations. Essentially, the application I/O profile helps in understanding why the network has traffic or congestion. 存储网络中的流量是应用程序启动读取或写入 I/O 操作的直接结果。因此，通过分析应用程序 I/O 配置文件，如 I/O 操作的时间、大小、类型和速率，可以更好地了解网络流量模式。从本质上讲，应用程序 I/O 配置文件有助于理解网络出现流量或拥塞的原因。

Chapter 5 explains solving congestion by storage I/O performance monitoring. The same details, at least conceptually, also apply to FCoE and RoCE (except the transport protocol differences) because the upper layers (SCSI and NVMe) are the same. Before proceeding, please refer to the following sections in Chapter 5, which are not repeated here for the sake of brevity. 第 5 章介绍了如何通过存储 I/O 性能监控解决拥塞问题。由于上层（SCSI 和 NVMe）相同，因此相同的细节（至少在概念上）也适用于 FCoE 和 RoCE（传输协议不同除外）。在继续阅读之前，请参考第 5 章中的以下章节，为简洁起见，此处不再赘述。

 Chapter 5, the section on Why Monitor Storage I/O Performance? explains the basic value of monitoring storage I/O performance. 第 5 章 "为什么要监控存储 I/O 性能？"一节介绍了监控存储 I/O 性能的基本价值。

 Chapter 5, the section on How and Where to Monitor Storage I/O Performance explains three locations for storage I/O performance monitoring—hosts, storage arrays, or the network. 第 5 章 "如何以及在何处监控存储 I/O 性能 "一节介绍了监控存储 I/O 性能的三个位置--主机、存储阵列或网络。

 Chapter 5, the section on Cisco SAN Analytics explains how Cisco MDS switches monitors storage I/O performance natively within the switches. This capability is called SAN Analytics and it is available only on the Fibre Channel ports. This section also helps in understanding why a similar capability does not exist on Ethernet switches. 第 5 章 "Cisco SAN Analytics "一节介绍了 Cisco MDS 交换机如何在交换机内部监控存储 I/O 性能。这种功能称为 SAN Analytics，仅在光纤通道端口上可用。本节还有助于理解为什么以太网交换机不具备类似功能。

 Chapter 5, the section on Understanding I/O Flows in a Storage Network helps in understanding the difference between I/O flows in Fibre Channel fabrics versus lossless Ethernet networks. Pay special attention to the sub-section on I/O Flows versus I/O Operations. 第 5 章 "了解存储网络中的 I/O 流量 "一节有助于了解光纤通道结构中的 I/O 流量与无