BSDCan2012 - Slide Update J

BSDCan 2012
The Technical BSD Conference

Luigi Rizzo
Day Talks - 2 - 2012-05-12
Room MRT 212
Start time 10:00
Duration 01:00
ID 303
Event type Lecture
Track Hacking
Language used for presentation English

High speed packet I/O: challenges and solutions.

The netmap framework for fast packet I/O

Dealing with millions of packets per second, as it can happen on 10 Gbit interfaces, puts under stress both hardware and software.

Most OSes (*BSD, Linux, Windows) are unable to handle more than 1Mpps per core, barely enough for MSS-sized traffic at 10 Gbit/s. After years of incremental improvements (interrupt mitigation, polling, multiqueue NICs, nic offloading) we recently took a very radical approach with the netmap framework, which completely redefines the device driver API and the interface with applications. Netmap provides 10-20x speedups for certain tasks (generators, traffic monitors, packet forwarding), and its use can help improving more common tasks (TCP) and point out other performance bottlenecks that are usually hidden by the current low speed I/O subsystems.

This talk will discuss challenges existing in the current packet I/O frameworks, describe the key ideas used by Netmap, and present the current status and future goals.