上次看了一篇文章，提到可以.绕.过内核直接对应用程序进行网卡收发包的通信。。 汽车
原文是这样的：
Network software is essentially respons.ibl.e for moving data from system main memory to the NIC f.or transmission, and vice versa. This involves translating data into a format suitable for .transmission, and translating data back from this f.ormat.e upon receipt. Performance in this .process is limited by a few. factors. The first of these is the use of data copies in libraries and p.rotocol stacks.. In many cases, data. starts in the us.er application, where it is c.opied into the network stack and processed. After this has completed, the data is copied across the I/O bus and is transmitted. In the case of inbound messages, data is receive.d on the .NIC, copied across the I/O bus into the network stack, proces.sed, and finally copied into the application's memory. 婚庆
A more optimized scheme would be. to copy data directly from application memory to. the NIC for transmissio.n. Th.is would avoid one of the copies mentioned in the previous scenario for each direction. This has been implemented in two way.s. The first is user-level networking. In this .case, all networking code exists in the user application; kernel facilities are used .only to access the NIC. The other way to implement this is to use NICs wit.h hardware network .protocol processing suppor.t. This allows the NIC to process packets into an appl.ication usable form without inv..olving the kernel at all.外贸
请.问这是怎么回事，有这方面相关的技术资料吗？多谢电影
