The operating system kernel needs to provide a complete I/O control process and prepare a large number of various data structures to manage the flow of I/O between various modules.   These modules include: VFS directory layer, Page Cache layer, file system layer, network processing layer, common block layer, I/O scheduler layer, block device driver layer, external I/O channel controller driver layer. These layers together form a large and complex I/O protocol stack.   I'm sure you already have an idea of how programs use I/O devices. The most common I/O devices fall into three categories: network card devices, storage devices（st2400mm0129）， and interactive devices such as keyboards/mice. These devices can be connected to the system through PCIE or USB ports. The question is, how is the data sent to them generated and sent all the way to the device driver and to the device?   If a user mode program wants to read the contents of sector 0 of a hard disk fan, it cannot directly manipulate the hard disk, because it cannot call the functions provided by the hard disk device driver at all, it can only delegate the kernel code to do this through the read system call.   In the parameters of the read system call, the user side program must at least tell the kernel: which device to read, which bytes of the device to read from, where to put the data read back into memory, and other parameters (such as what way to read when reading, etc.). The same goes for reading files. 

The LPe32002-M2 is a high-performance Fibre Channel adapter from Emulex. The following is a detailed introduction to it:   Fibre Channel technology: The LPe32002-M2 uses 8Gb/s or 16Gb/s Fibre Channel technology to connect storage devices and host servers for high-speed data transmission and storage area network (SAN) connectivity.   Performance optimization: The adapter has excellent performance characteristics and supports high-speed, low-latency data transfer. It can meet the high demand for storage bandwidth and I/O applications, such as virtualized environments, large databases and online transaction processing.   High Availability: The LPe32002-M2 provides several high availability features, including interleaved path redundancy (IPR), dynamic path selection (DPS), and multipath failover (MPFA). These functions improve the redundancy and fault tolerance of the storage system to ensure data reliability and availability.   Simplified administration: The adapter supports Emulex OneCommand Manager applications, simplifying the deployment, configuration, and administration of the adapter. Administrators can easily monitor adapter status, perform diagnostics and troubleshooting, and perform firmware upgrades.   Compatibility: The LPe32002-M2 adapter has a wide range of compatibility and can be used with multiple operating systems and storage devices. It supports major server operating systems such as Windows, Linux, and VMware, as well as storage switches and storage devices that interoperate with other Fibre Channel products.   In summary, the LPe32002-M2 is a high-performance Fibre Channel adapter for storage area network environments for fast and reliable data transfer. With high availability features and simplified management functions, it is compatible with a variety of operating systems and storage devices, providing enterprises with efficient storage solutions.   Trust the Expertise of Over 10 Years in the Industry. Choose the LPE32002-M2 Fiber Card for Unparalleled Performance and Reliability. STOR Technology Limited allows you to experience high performance at factory prices. ODM orders Welcome!