linux -爱代码爱编程
一、简介 1、什么是内核参数(kernel parameters at runtime) 内核参数是可在系统运行时调整的可调整参数。不需要重启或重新编译内核就可以使更改生效。可以通过以下方法处理内核参数: sysctl
代码编织梦想
一、简介 1、什么是内核参数(kernel parameters at runtime) 内核参数是可在系统运行时调整的可调整参数。不需要重启或重新编译内核就可以使更改生效。可以通过以下方法处理内核参数: sysctl
Modified TCP Implementations Standard TCP with ECN detects the presence of congestion and reacts to it by reducing the congestion window as if packets had been dropped. In data c
Configuring versus Operating a Shared Storage Network Another important consideration is the operational state of a network. Just because a network is configured for sharing, doe
Goals The end-to-end flow control and congestion control mechanisms of TCP are enabled by default and no user intervention is needed. But these mechanisms, including ECN, are not
记录一下实验过程,方便后续回顾 一、Dhrystone简介 Dhrystone是测量处理器运算能力的最常见基准程序之一,常用于处理器的整型运算性能的测量。程序是用C语言编写的,因此C编译器的编译效率对测试结果也
Queue Depth Monitoring and Microburst Detection Queue depth monitoring and microburst detection capture the events that may cause congestion at a lower granularity but are unnoti
Bit Errors in Lossy Ethernet Networks with TCP Transport As explained in Chapter 1, when a bit stream is exchanged over a network, some bits may be altered resulting in bit error
TCP Flow Monitoring versus I/O Flow Monitoring TCP flow monitoring shouldn’t be confused with I/O flow monitoring because of the following reasons: TCP 流量监控不应与 I/O 流量监控混淆,原因如下:
Switch Buffer Management Recall that during network congestion, a TCP sender relies on the following events for reducing its transmission rate. 回想一下,在网络拥塞期间,TCP 发送端依靠以下事件来降低传输速率。
Comparison with Lossless Networks As Chapter 2 explains, Fibre Channel defines a maximum frame size of 2148 bytes. Users do not have to change the MTU value, and hence, it is nev
Comparison with RoCEv2 Networks RoCEv2 Congestion Management (explained in Chapter 7) uses the same mechanism as ECN in TCP/IP networks. Compare Figure 8-103 with Figure 7-17 in
Congestion Avoidance When the sender’s upper layer desires to send more data, TCP throughput increases assuming that the receiver-window is not a limiting factor. But this increa
Congestion Notification in TCP Storage Networks Congestion Notification in TCP storage networks is achieved by Explicit Congestion Notification (ECN), which is standardized by RF
Active Queue Management As previously mentioned, dropping or marking schemes for packets that are waiting in a queue can significantly influence TCP’s behavior on the end devices
原子操作和原语是计算机科学中常见的概念,通常用于多线程或多进程环境中,以确保数据的一致性和同步。 原子操作(Atomic Operations) 原子操作是不可再分的操作,在执行完毕之前不会被线程调度系统中断的操作。从外部看,一个原子操作要么是完全执行完成的,要么是未执行的,没有中间状态。这种特性使原子操作成为实现同步机制如互斥锁(mutexes)和信
Selective Acknowledgment (SACK) Some TCP implementations use Selective Acknowledgment (SACK), which increases performance during packet drops by selectively acknowledging only th
Congestion Due to Over-utilization of the Target Link The same problem may happen on a target/storage link when multiple hosts initiate large-size write I/O operations to the sam
NVMe/TCP I/O Operations Figure 8-7 shows NVMe/TCP Read I/O Operation. A host (initiator) initiates a read I/O operation over a TCP connection to the target, which is called a con
per-CPU变量 per-CPU变量是一种存在与每个CPU本地的变量,对于每一种per-CPU变量,每个CPU在本地都有一份它的副本。 per-CPU变量的优点 多处理器系统(smp)中无需考虑与其他处理器的竞争问题
Layer 2 Priority Flow Control As Figure 7-4 shows, at layer 2 of the OSI model, traffic is assigned to different VLANs by adding an IEEE 802.1Q VLAN header. This VLAN header cont