It is well-suited to implement firewalls that need to pass on traffic to the network stack ( xdp-ddos). It is a default part of the Linux kernel nowadays and hence very well integrated. XDP is technically not a user space framework: the code is compiled to eBPF which is run by a JIT in the kernel, this restricts the choice of programming language to those that can target eBPF bytecode (typically a restricted subset of C is used). Netmap (a standard component in FreeBSD and also available on Linux) offers interfaces to pass packets between the kernel network stack and a user space app, it can even make use of the kernel’s TCP/IP stack with StackMap ( stackmap).įurther, netmap supports using a NIC with both netmap and the kernel simultaneously by using hardware filters to steer packets to receive queues either managed by netmap or the kernel ( cloudflare-netmap). Netmap ( netmap) and XDP ( xdp) are good examples of integrating kernel components with specialized applications. Ixy’s receive and transmit path for the same driver is only 127 lines of code. It is possible to read and understand drivers found in other frameworks, but ixy’s driver is at least an order of magnitude simpler than other implementations.įor example, DPDK’s implementation of the ixgbe driver needs 5,400 lines of code just to handle receiving and sending packets in a highly optimized way, offering multiple paths using different vector SIMD instruction sets. Section 6).Ī packet forwarding application is less than 1,000 lines of C code including the whole poll-mode driver, the implementation is discussed in Section 4 We currently support the Intel ixgbe family of NICs (cf. Our whole architecture, described in Section 3, aims at simplicity and is trimmed down to the bare minimum. Ixy is designed for educational use only, i.e., you are meant to use it to understand how user space packet frameworks and drivers work, not to use it in a production environment. We present ixy, a user space packet framework that is architecturally similar to DPDK ( dpdk) and Snabb ( snabb).īoth use full user space drivers, unlike netmap ( netmap), PF_RING ( pfring), PFQ ( pfq), or similar frameworks that rely on a kernel driver. Our code is available as free and open source under the BSD license at VirtIO support ensures that everyone can run it in Performance on a stripped-down implementation to assess individual The former allows us to reason about driver and framework Implementations of drivers for both the Intel 82599 family and for virtual This paper is partially written in tutorial style on the case study of our The whole NIC driver uses less than 1,000 lines of C code. ixy focuses on theīare essentials of user space packet processing: a packet forwarder including Network driver designed for simplicity and educational purposes to show thatįast packet IO is not black magic but careful engineering. Network applications should understand the intricacies of the underlyingĭrivers, especially if they impact performance. We want to change this: every researcher building high-speed These barriers are gone nowadays, yetĭevelopers still treat user space drivers as black-boxes magically acceleratingĪpplications. Previously,ĭriver code was hidden in the kernel and rarely modified, or even looked at, byĭevelopers working at higher layers. Makes low-level code more accessible to developers and researchers. The rise of user space packet processing frameworks like DPDK and netmap
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |