maxxfire
“用户态通信协议”。。。
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。。
原文是这样的：
Network software is essentially responsible for moving data from system main memory to the NIC for transmission, and vice versa. This involves translating data into a format suitable for transmission, and translating data back from this formate 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 protocol stacks. In many cases, data starts in the user application, where it is copied 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 received on the NIC, copied across the I/O bus into the network stack, processed, and finally copied into the application's memory.
A more optimized scheme would be to copy data directly from application memory to the NIC for transmission. This would avoid one of the copies mentioned in the previous scenario for each direction. This has been implemented in two ways. 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 with hardware network protocol processing support. This allows the NIC to process packets into an application usable form without involving the kernel at all.
请问这是怎么回事，有这方面相关的技术资料吗？多谢