You're only half right - projects attempting to achieve very high speed networking (packets per second) go to great lengths to remove the traditional syscall pe

You're only half right - projects attempting to achieve very high speed networking (packets per second) go to great lengths to remove the traditional syscall per packet that normal linux networking involves. One approach to this is to move everything into userspace and take the kernel out of it completely. Another approach used by some projects is to put everything into the kernel and take userspace out of it completely. Either of these approaches remove syscalls. The kernel isn't an inherently slower place (in some cases it can be faster as you have more control), it is having your network stack split across the kernel/userspace boundary that is slow.