The Data Plane Development Kit (DPDK) is an

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...

software project managed by the

Linux Foundation The Linux Foundation (LF) is a non-profit technology consortium founded in 2000 as a merger between Open Source Development Labs and the Free Standards Group to standardize Linux, support its growth, and promote its commercial adoption. Addi ...

. It provides a set of

data plane In routing, the forwarding plane, sometimes called the data plane or user plane, defines the part of the router architecture that decides what to do with packets arriving on an inbound interface. Most commonly, it refers to a table in which the ...

libraries and

network interface controller A network interface controller (NIC, also known as a network interface card, network adapter, LAN adapter or physical network interface, and by similar terms) is a computer hardware component that connects a computer to a computer network. E ...

polling-mode drivers for offloading TCP

packet processing In digital communications networks, packet processing refers to the wide variety of algorithms that are applied to a packet of data or information as it moves through the various network elements of a communications network. With the increased p ...

from the

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

kernel Kernel may refer to: Computing * Kernel (operating system), the central component of most operating systems * Kernel (image processing), a matrix used for image convolution * Compute kernel, in GPGPU programming * Kernel method, in machine lea ...

processes A process is a series or set of activities that interact to produce a result; it may occur once-only or be recurrent or periodic. Things called a process include: Business and management *Business process, activities that produce a specific se ...

running in

user space A modern computer operating system usually segregates virtual memory into user space and kernel space. Primarily, this separation serves to provide memory protection and hardware protection from malicious or errant software behaviour. Kerne ...

. This offloading achieves higher computing efficiency and higher packet throughput than is possible using the interrupt-driven processing provided in the kernel. DPDK provides a programming framework for x86,

ARM In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint (shoulder joint) and the elbow joint. The distal part of the upper limb between t ...

, and

PowerPC PowerPC (with the backronym Performance Optimization With Enhanced RISC – Performance Computing, sometimes abbreviated as PPC) is a reduced instruction set computer (RISC) instruction set architecture (ISA) created by the 1991 Apple– IBM ...

processors and enables faster development of high speed data packet networking applications. It scales from mobile processors, such as

Intel Atom Intel Atom is the brand name for a line of IA-32 and x86-64 instruction set ultra-low-voltage processors by Intel Corporation designed to reduce electric consumption and power dissipation in comparison with ordinary processors of the Intel ...

, to server-grade processors, such as

Intel Xeon Xeon ( ) is a brand of x86 microprocessors designed, manufactured, and marketed by Intel, targeted at the non-consumer workstation, server, and embedded system markets. It was introduced in June 1998. Xeon processors are based on the sa ...

. It supports

instruction set architecture In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ...

s such as Intel, IBM

POWER8 POWER8 is a family of superscalar multi-core microprocessors based on the Power ISA, announced in August 2013 at the Hot Chips conference. The designs are available for licensing under the OpenPOWER Foundation, which is the first time for ...

, EZchip, and

. It is provided and supported under the open-source

BSD license BSD licenses are a family of permissive free software licenses, imposing minimal restrictions on the use and distribution of covered software. This is in contrast to copyleft licenses, which have share-alike requirements. The original BSD li ...

. DPDK was created by Intel engineer Venky Venkatesan, who is affectionately known as "The Father of DPDK." He died in 2018 after a long battle with cancer.

Overview

The DPDK framework creates a set of libraries for specific hardware/software environments through the creation of an Environment Abstraction Layer (EAL). The EAL hides the environment specifics and provides a standard programming interface to libraries, available hardware accelerators and other hardware and operating system (Linux, FreeBSD) elements. Once the EAL is created for a specific environment, developers link to the library to create their applications. For instance, EAL provides the frameworks to support

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which i ...

FreeBSD FreeBSD is a free and open-source Unix-like operating system descended from the Berkeley Software Distribution (BSD), which was based on Research Unix. The first version of FreeBSD was released in 1993. In 2005, FreeBSD was the most popular ...

, Intel IA- 32 or

64-bit In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit CPUs and ALUs are those that are based on processor registers, address buses, or data buses of that size. A comp ...

, IBM

POWER9 POWER9 is a family of superscalar, multithreading, multi-core microprocessors produced by IBM, based on the Power ISA. It was announced in August 2016. The POWER9-based processors are being manufactured using a 14 nm FinFET process ...

and

32- or 64-bit. The EAL also provides additional services including time references, generic

bus A bus (contracted from omnibus, with variants multibus, motorbus, autobus, etc.) is a road vehicle that carries significantly more passengers than an average car or van. It is most commonly used in public transport, but is also in use for cha ...

access, trace and debug functions and alarm operations. Using DPDK libraries one can implement a low overhead

run-to-completion Run-to-completion scheduling or nonpreemptive scheduling is a scheduling model in which each task runs until it either finishes, or explicitly yields control back to the scheduler. Run to completion systems typically have an event queue which is ...

, pipeline or staged, event driven, or hybrid model completely in userspace eliminating kernel and kernel to user copy. Hardware assists from NIC/Regex/Accelerators, libraries enhanced to make use of Intelligence Storage Acceleration (ISA) for bulk performance and accessing devices via

polling Poll, polled, or polling may refer to: Figurative head counts * Poll, a formal election ** Election verification exit poll, a survey taken to verify election counts ** Polling, voting to make decisions or determine opinions ** Polling places o ...

helps to eliminate the performance overhead of

interrupt In digital computers, an interrupt (sometimes referred to as a trap) is a request for the processor to ''interrupt'' currently executing code (when permitted), so that the event can be processed in a timely manner. If the request is accepted ...

too. Hugepages are used for large memory pool allocation, to decrease the amount of lookups and page management. The DPDK also includes software examples that highlight best practices for software architecture, tips for data structure design and storage, application profiling and performance tuning utilities and tips that address common network performance deficits.

Libraries

The DPDK includes data plane libraries and optimized

(NIC) drivers for the following: * A queue manager implements lockless queues * A buffer manager pre-allocates fixed size buffers * A memory manager allocates pools of objects in memory and uses a ring to store free objects; ensures that objects are spread equally on all

DRAM Dynamic random-access memory (dynamic RAM or DRAM) is a type of random-access semiconductor memory that stores each bit of data in a memory cell, usually consisting of a tiny capacitor and a transistor, both typically based on metal-oxi ...

channels * Poll mode drivers (PMD) are designed to work without asynchronous notifications, reducing overhead * A packet framework – a set of libraries that are helpers to develop packet processing All libraries are stored in the dpdk/lib/librte_* directories

Plugins

The DPDK includes drivers for many hardware types. There have been some additional out-of-tree plugin drivers in the past, which are now considered deprecated. * provides PMD

Ethernet Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in ...

layer supporting Vmxnet3 paravirtualized NIC; superseded by full VMXNET3 support in native DPDK. * provides a Virtual PMD Ethernet layer through shared memory based on 2 memory copies of packets

Environment

The DPDK was originally designed to run using a

bare-metal In computer science, bare machine (or bare metal) refers to a computer executing instructions directly on logic hardware without an intervening operating system. Modern operating systems evolved through various stages, from elementary to the pr ...

mode which is currently deprecated. Actually, DPDK's EAL provides support for Linux or FreeBSD userland application. EAL can be extended in order to support any processors.

Ecosystem

DPDK is now an open-source project under the

, supported by many companies. DPDK is governed by a Governing Board. The technical activities are overseen by a Technical Board. Beside

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the devel ...

, which is a contributor to the DPDK, several other vendors also support the DPDK within their products and some offer additional training, support and professional services. The list of vendors who have announced DPDK support includes: 6WIND, ALTEN Calsoft Labs, Advantech, Brocade, Big Switch Networks,

Mellanox Technologies Mellanox Technologies Ltd. ( he, מלאנוקס טכנולוגיות בע"מ) was an Israeli-American multinational supplier of computer networking products based on InfiniBand and Ethernet technology. Mellanox offered adapters, switches, softwa ...

Radisys Radisys Corporation is an American technology company located in Hillsboro, Oregon, United States that makes technology used by telecommunications companies in mobile networks. Founded in 1987 in Oregon by former employees of Intel, the company w ...

, Tieto, Wind River, Lanner. and

NXP NXP Semiconductors N.V. (NXP) is a Dutch semiconductor designer and manufacturer with headquarters in Eindhoven, Netherlands. The company employs approximately 31,000 people in more than 30 countries. NXP reported revenue of $11.06 billion in 2 ...

Projects

The

pfSense pfSense is a firewall/ router computer software distribution based on FreeBSD. The open source pfSense Community Edition (CE) and pfSense Plus is installed on a physical computer or a virtual machine to make a dedicated firewall/router for a ...

project published a road map on 25 February 2015, in which developer Jim Thompson announced the rewriting of the pfSense core—including pf,

network packet In telecommunications and computer networking, a network packet is a formatted unit of data carried by a packet-switched network. A packet consists of control information and user data; the latter is also known as the '' payload''. Control infor ...

forwarding and shaping,

link bonding In computer networking, link aggregation is the combining (wikt:aggregation, aggregating) of multiple network connections in parallel by any of several methods, in order to increase throughput beyond what a single connection could sustain, to ...

IPsec In computing, Internet Protocol Security (IPsec) is a secure network protocol suite that authenticates and encrypts packets of data to provide secure encrypted communication between two computers over an Internet Protocol network. It is used in ...

—using DPDK: "We have a goal of being able to forward, with packet filtering at rates of at least 14.88 Mpps. This is 'line rate' on a 10 Gbps interface. There is simply no way to use today's FreeBSD (or linux) in-kernel stacks for this type of load."

Open vSwitch Open vSwitch, sometimes abbreviated as OVS, is an open-source implementation of a distributed virtual multilayer switch. The main purpose of Open vSwitch is to provide a switching stack for hardware virtualization environments, while supportin ...

(OVS) has a limited set of features running userland that can be leveraged to bypass the Linux kernel OVS processing. This use case of OVS with DPDK userland is usually named OVS-DPDK. It is mostly deployed with

OpenStack OpenStack is a free, open standard cloud computing platform. It is mostly deployed as infrastructure-as-a-service (IaaS) in both public and private clouds where virtual servers and other resources are made available to users. The software platfo ...

Neutron but it assumes that many features and

software-defined networking Software-defined networking (SDN) technology is an approach to network management that enables dynamic, programmatically efficient network configuration in order to improve network performance and monitoring, making it more like cloud computing ...

(SDN) capabilities of Openstack are disabled. For instance, when OVS-DPDK is used, Neutron provides a lower level of security than when OVS kernel is used (no stateful firewalling, less security group). The FD.IO VPP platform is an extensible framework that provides out-of-the-box production quality switch/router functionality. It is the open source version of Cisco's

Vector Packet Processing Vector Packet Processing (VPP) platform is an extensible, open-source framework, which offers the functionality of network switches or routers. V''ector processing'' is the process of processing multiple packets at a time, with low latency. Single p ...

(VPP) technology: a high performance, packet-processing stack that can run on commodity CPUs, and can leverage the Poll Mode Drivers for both NICs and cryptographic acceleration hardware and libraries. VPP supports and uses the DPDK library. TRex is an open source traffic generator using DPDK. It generates L4–7 traffic based on pre-processing and smart replay of real traffic templates. TRex amplifies both client and server side traffic and can scale to 200 Gbit/s with one UCS using Intel XL710. TRex also supports multiple streams, ability to change any packet field and provides per stream statistics, latency and jitter. DTS (DPDK Test Suite) is a Python-based framework for functional tests and benchmarks. It is an open-source project, started in 2014, and is hosted on dpdk.org. It supports both software traffic generators like Scapy and dpdk-pktgen, and a hardware traffic generator like

Ixia ''Ixia'' is a genus of cormous plants native to South Africa from the family Iridaceae. Some of them are known as the corn lily. Some distinctive traits include sword-like leaves and long wiry stems with star-shaped flowers. It usually prefer ...

. DPDK has support for several

SRIOV In virtualization, single root input/output virtualization (SR-IOV) is a specification that allows the isolation of PCI Express resources for manageability and performance reasons. Details A single physical PCI Express bus can be shared in a virt ...

network drivers, enabling creating a PF (Physical Function) and VFs, and also to launch VMs (like

QEMU QEMU is a free and open-source emulator (Quick EMUlator). It emulates the machine's processor through dynamic binary translation and provides a set of different hardware and device models for the machine, enabling it to run a variety of g ...

VMs) and assign VFs to them using PCI Passthrough DDP (Dynamic Device Personalization) is one of the new advanced features implemented with DPDK. It allows you to load firmware for a device dynamically, without resetting the host.Rami Rosen
DPDK in depth
Kernel TLV, August 2018

References

{{Routing software Free routing software Networking hardware Linux Foundation projects Software using the BSD license