On Oct 14 16:33:23, mikael.tr...@gmail.com wrote: > Most devices in a system can be accessed with good performance from > userland as it is now, for instance block devices, USB, serial ports, video > and audio.
Repeat after me: userland is not supposed to "access devices". It is supposed to talk to a defined interface and let thr kernel talk to the device. > Ethernet is a rare exception and NetMap solved this in a neat way - > Prior to NetMap, those who wanted to make high-performance ethernet IO in > userland would run their app as root and effectively implement NIC hardware > drivers in userland. NetMap generalized this entire problem to one > hardware-agnostic interface. Repeat after me: it is kernel's job to "make high-performance ethernet IO".
