Dpdk memory channels Alternative ecosystem 9. /Bruce Panu Matilainen The number of memory channels is a truly obscure thing as a mandatory 7. 11, this article It provides some other optional services, such as a per-core object cache and an alignment helper to ensure that objects are padded to spread them equally on all RAM channels. The NIC driver pre-allocates kernel memory buffers where the packets are stored The NIC driver pre-allocate the transmit (TX) and receive (RX) ring buffer in the memory For optimum OVS-DPDK performance, reserve a block of memory local to the NUMA node. In the DPDK, it is identified by name and uses a mempool handler to store free objects. This 6. --iova-mode <pa|va> Force RTE Mempool. 6 3. Optionally install dpdk-devel or dpdk-dev on distros with precompiled DPDK packages, and compile 什么是内存通道（channel）？ 在数电和计算机硬件领域， 多通道内存架构 是一种技术。 内存和CPU上的 内存控制器，通过总线来和计算机的其余部分进行通信。在内存和内存控制器之间增加通信通道，可以加快数据传输速率。 内存控制器通常有一个通道、两个通道（双通道）、四通道（四通道 May 20, 2024 · 注：DPDK会将当前进程管理的所有memory，都写入iommu表，即使某个设备只使用自己分配的memory，用于DMA。 这样管理比较粗放，但是也有自己的好处，不需要各个驱动程序自己写iommu表，DPDK底层架构统一处理，使用者不感知。 Fig. h. 1. Compiling DPDKStack Ceph dpdkstack is not compiled by default. -m <megabytes> Amount of memory to preallocate at startup. Control Functions 4. This means that multiple ports can share the same mempool. Mar 23, 2018 · The number of memory channels we specify with -n does not do much: it just aligned each memory pool element to a different memory channel as described in DPDK Programmer's Guide Even if we put an invalid number there, we still should be able to use all of the channels, maybe not that optimal. Help Functions 4. -n NUM Set the number of memory channels to use. PMD Driver 47. This 9. Communication Between lcores 66. so : Add driver (can be used multiple times) -m MB : Memory to allocate (see also --socket-mem) -r NUM : Force number of memory ranks (don't detect) --xen-dom0 : Support application running on 9. It provides some other optional services such as a per-core object cache and an alignment helper to ensure that objects are padded to spread them equally on all DRAM or DDR3 channels Here we are connecting the ports to an external DPDK packet Generator, so we will set the MAC addresses in the DPDK traffic generator to match those of the external system that will run the DPDK packet framework. In particular, picking the right kernel driver and IOVA mode may be crucial, depending on the Jun 5, 2024 · The performance of DPDK relies on various factors such as memory access latency, I/O throughput, CPU performance, etc. Memory This section describes some key memory considerations when developing applications in the 6. Locking memory pages 65. It then introduces you to the Data Plane Performance Demonstrator. 1 MAC data plane pipeline with DPDK on an Intel® Xeon® platform To fully use quad channel memory, I have to use 4 separated DRAM, installed on different memory slots of my motherboard. Direct Memory Access (DMA) Device Library The DMA library provides a DMA device framework for management and provisioning of hardware and software DMA poll mode drivers, defining generic API which support a number of different DMA operations. NUMA 70. DPDK device memory can be allocated in one of two ways in OVS DPDK, shared memory or per port memory. Memory-related options --legacy-mem Use legacy DPDK memory allocation mode. --iova-mode <pa|va> Force Oct 10, 2018 · Learn how to configure and run the Data Plane Development (DPDK) Test Suite 17. Branch Prediction 70. --in-memory Do not create any shared data structures and run 2. Number of DMA mappings is limited by kernel with user locked memory limit of a process (rlimit) for system/hugepage memory. Mbuf Library The mbuf library provides the ability to allocate and free buffers (mbufs) that may be used by the DPDK application to store message buffers. Coding Considerations 65. Distribution Across Memory Channels 66. If there are two or its multiple, it might be dual-channel, if there are three or its multiple it might be triple-channel, if there are four or its multiple it might be quad-channel. Running the Application 3. 8. However, DPDK is a complex beast that needs to be configured correctly to make the most out of it. This library is used by the Mbuf Library and the 9. By default OVS DPDK uses a shared memory model. Therefore, it ensures that the packet header is interleaved optimally across the channels and ranks for L3 processing. Locks and Atomic Operations 65. It provides some other optional services such as a per-core object cache and an alignment helper to ensure that objects are padded to spread them equally on all DRAM or DDR3 channels. Branch Prediction 65. 1 Memory Sharing in the DPDK Multi-process Sample Application Fig. Depending on hardware memory configuration on X86 architecture, performance can be greatly improved by adding a specific padding between objects. Lower Packet Latency 47. Atomic Operations: Use C11 Atomic Builtins 70. NUMA 66. Writing Efficient Code This chapter provides some tips for developing efficient code using the DPDK. Buffers Stored in Memory Pools The Buffer Manager uses the Mempool Library to allocate buffers. You can check the memory configuration using dmidecode as follows: Mar 20, 2025 · 文章浏览阅读8. Note As a general guideline, it is recommended to populate at least one memory DIMM in each memory channel. This memory is exposed to DPDK service layers such as the Memory Pool Library. Dec 5, 2022 · EAL arguments: n number of memory channels r number of memory ranks m amount of memory to preallocate at startup in-memory no shared data structures IOVA mode huge-worker-stack My setup: 2 x Intel Xeon Gold 6348 CPU @ 2. For example: --socket-mem 1024,2048 This will allocate 1 gigabyte of memory on socket 0, and 2048 megabytes of The -n command is used to select the number of memory channels. In my case with 6 channels I should be doing 90GB/s . --iova-mode <pa|va> Force Dec 26, 2018 · Optimize memory usage of multithreaded DOCSIS 3. Returns The number of memory channels on the system. 21. Testpmd Multi-Process Command-line Options 4. Use hugepages to reduce memory access latency and improve cache efficiency. The value is 0 if unknown or not the same on all devices. Locking memory pages 66. This optimizes entries of mempool or ring structure to interleave memory access into n-ways. EAL in a Linux-userland Execution Environment In a Linux user space environment, the DPDK application runs as a user-space application using the pthread library. Introduction 2. Optionally install dpdk-devel or dpdk-dev on distros with precompiled DPDK packages, and compile Jul 1, 2019 · This is the final article in the series about how memory management works in the Data Plane Development Kit (DPDK). 5 Ghz Hyperthreading disabled Ubuntu 22. Its uses are many—packet I/O, crypto operations, event scheduling, and many other use cases that need to quickly allocate or deallocate fixed-sized buffers. For example when a port is added it will have a given MTU and socket ID associated with it. that would be amazing! Copy the DPDK application binary to your target, then run the application as follows (assuming the platform has four memory channels per processor socket, and that cores 0-3 are present and are to be used for running the application): On application start-up in a primary or standalone process, the DPDK records to memory-mapped files the details of the memory configuration it is using - hugepages in use, the virtual addresses they are mapped at, the number of memory channels present, etc. This 12. 6 7. Hugepage Memory Use by Applications When running an application, it is recommended to use the same amount of memory as that allocated for hugepages. Locks 70. Communication Between lcores 47. Users may use the code to understand some of the techniques employed, to build upon for prototyping or to add their own protocol stacks. Distribution Across Memory Channels 47. Copy the DPDK application binary to your target, then run the application as follows (assuming the platform has four memory channels per processor socket, and that cores 0-3 are present and are to be used for running the application): 5. Start packet forwarding in the testpmd application with the start command. Optionally install dpdk-devel or dpdk-dev on distros with precompiled DPDK packages, and compile Dec 5, 2024 · Learn how VPP optimizes CPU usage, manages packet buffers, integrates with DPDK, and minimizes thread communication for unmatched efficiency. quit 4. Jul 3, 2019 · Part 1 covers why memory management in DPDK works the way it does, and what the principles are that lie behind it. If there’s just one, it cannot be using multichannel memory. --iova-mode <pa|va> Force Hence DPDK’s memory is mapped in hugepage granularity or system page granularity. 4. show 66. -c COREMASK Set the hexadecimal bitmask of the cores to run on. 26. 2k次，点赞6次，收藏59次。本文深入解析RAM的两种主要类型：SRAM与DRAM，对比其结构与性能特点，阐述易失性与非易失性存储器的区别，并详细描述了现代计算机内存子系统的架构，包括channel、DIMM、rank、chip、bank、row与column等关键组成部分。 Shared memory packet interface (memif) PMD allows for DPDK and any other client using memif (DPDK, VPP, libmemif) to communicate using shared memory. Hardware and Memory Requirements For best performance use an Intel Xeon class server system such as Ivy Bridge, Haswell or newer. Locks 66. Profile Your Application 48. Setting tx-offload to 0x8000 and the maximum packet length to 9600 (CRC included) makes input Jumbo Frames to be stored in multiple buffers by the hardware RX engine. Once the Sep 14, 2019 · By Antanoly Burakov This post is Part 2 of a 4-part blog series that was originally published on the Intel Developer Zone blog. You can check the memory configuration using dmidecode as follows: 14. 3 vHost-net Architecture Overview Fig. stop 4. Mempool Library A memory pool is an allocator of a fixed-sized object. 11. -r, --memory-ranks <number of ranks> Set the number of memory ranks (auto-detected by default). 1 LTS Kernel 5. Command File Functions 4. I did lscpu 13. --iova-mode <pa|va> Force Copy the DPDK application binary to your target, then run the application as follows (assuming the platform has four memory channels per processor socket, and that cores 0-3 are present and are to be used for running the application): Copy the DPDK application binary to your target, then run the application as follows (assuming the platform has four memory channels per processor socket, and that cores 0-3 are present and are to be used for running the application): Apr 24, 2025 · Optimizing memory and PCIe settings can significantly impact DPDK performance. Design Principles The DMA framework provides a generic DMA device framework which supports both physical (hardware) and virtual (software) DMA 34. --iova-mode <pa|va> Force On application start-up in a primary or standalone process, the DPDK records to memory-mapped files the details of the memory configuration it is using - hugepages in use, the virtual addresses they are mapped at, the number of memory channels present, etc. Basic Multi-process Example ¶ The examples/simple_mp folder in the DPDK release contains a basic example application to demonstrate how two DPDK processes can work together using queues and memory pools to share information. DPDK application developers will benefit by implementing these optimization guidelines in their applications. Inline Functions 66. Ensure that each memory channel has at least one memory DIMM inserted, and that the memory size for each is at least 4GB. Coding Considerations 47. h rte_free void rte_free (void *ptr) rte_malloc void * rte_malloc (const char *type, size_t size, unsigned align) __rte_alloc_size (2) __rte_alloc_align (3) __rte_malloc __rte_dealloc_free rte_zmalloc void * rte_zmalloc (const char *type, size_t size, unsigned align) __rte_alloc_size (2) __rte_alloc_align (3) __rte_malloc __rte_dealloc_free rte_memory. 7. start tx_first 4. 4. In DPDK, the memory pool is identified by name, and uses a ring to manage free objects. Atomic Operations: Use C11 Atomic Builtins 66. Definition at line 29 of file rte_eal. --iova-mode <pa|va> Force Jul 3, 2019 · Introduction In the previous article, we covered the main concepts and principles behind Data Plane Development Kit (DPDK) memory management and how they contribute to DPDK’s unparalleled performance. EAL Command-line Options 3. h:332 rte_malloc. -m, --memory-size <megabytes> Amount of memory to preallocate at startup. The EAL performs physical memory allocation using mmap () in hugetlbfs (using huge page sizes to increase performance). For instance, page 0 may be located on channel 0, page 1 on channel 1, page 2 on channel 2, etc. Locks 65. Hi, I am new to DPDK and i tried searching the archives in case this had been discussed but couldnt find any references and hence this email: What is the significance of " -n NUM: Number of memory channels per processor socket" which is passed as an EAL option? I have a virtual machine (VM) spawned using VirtualBox and i am trying to use DPDK to get faster access to packets there. h rte 10. How to get best performance with NICs on Intel platforms This document is a step-by-step guide for getting high performance from DPDK applications on Intel platforms. Communication Between lcores 65. Jun 24, 2024 · ms_dpdk_hw_queue_weight ：可能用于配置 Monitor 服务在 DPDK 硬件队列中使用的权重。 DPDK 是一种用于优化网络性能的库，它提供了与硬件队列（如 NIC 队列）交互的能力。 注：DPDK会将当前进程管理的所有memory，都写入iommu表，即使某个设备只使用自己分配的memory，用于DMA。 这样管理比较粗放，但是也有自己的好处，不需要各个驱动程序自己写iommu表，DPDK底层架构统一处理，使用者不感知。 11. A rte_mbuf struct generally carries network packet buffers, but it can actually be any data (control data, events, …). On application start-up in a primary or standalone process, the DPDK records to memory-mapped files the details of the memory configuration it is using - hugepages in use, the virtual addresses they are mapped at, the number of memory channels present, etc. Each channel has a bandwidth limit, meaning that if all memory access operations are done on the first channel only, there is a potential bottleneck. The default mempool handler is ring based. Inline Functions 65. Jul 22, 2023 · 也就是说，即使DPDK内存池的主题出现在几乎所有关于DPDK内存管理的讨论中，从技术上讲，内存池管理器是一个建立在常规DPDK内存分配器之上的库。 In a Linux user space environment, the DPDK application runs as a user-space application using the pthread library. The message buffers are stored in a mempool, using the Mempool Library. PMD 65. 6 Ghz 28 cores per socket Max 3. PMD 66. 6 Magic number written by the main partition when ready. It is identified by its name, and uses a ring to store free objects. Branch Prediction 66. Our team want to allocate large blocks of contiguous physical m Currently, I have no idea to find out memory mapping of virtual machines. -n option optimizes memory bank access pattern for datastructures. Memif is Linux only. Introduction In the previous article, we covered the main concepts and principles behind Data Plane Development Kit (DPDK) memory management and how they contribute to DPDK’s unparalleled performance. The rte_mbuf header structure is kept as Memory channels ¶ Obtaining the correct number of memory channels (the -n argument) is tricky because it depends on how many channels the system board supports, the number and types of memory chips and how they are physically installed in the system and there’s no easy or even reliable way to tell from a running system. What is the significance of " -n NUM: Number of memory channels per processor socket" which is passed as an EAL option? I have a virtual machine (VM) spawned using VirtualBox and i am trying to use DPDK to get faster access to packets there. NUMA 65. --iova-mode <pa|va> Force 70. puppet-vswitch - Puppet provider for virtual switches. A problem well stated is a problem half-solved, thus the paper starts with profiling methodology to help identify the bottleneck in an application. --socket-mem <amounts of memory per socket> Preallocate specified amounts of memory per socket. 11. You can check the memory configuration using dmidecode as follows: Aug 9, 2016 · Abstract This paper illustrates best-known methods and performance optimizations used in the Data Plane Development Kit (DPDK). However, DPDK is a complex beast that needs to be configured On application start-up in a primary or standalone process, the DPDK records to memory-mapped files the details of the memory configuration it is using - hugepages in use, the virtual addresses they are mapped at, the number of memory channels present, etc. PMD 70. You can check the memory configuration using dmidecode as follows: Ethernet Poll Mode Driver (PMD) — Designed to work without asynchronous, interrupt-based signaling mechanisms. Choose NICs associated with the same NUMA node that you use for memory and CPU pinning. The objective is to ensure that the beginning of each object starts on a different channel and rank in memory so that all channels are equally loaded. I think -n 4 will work on both dual and quad channel memory. See The SPDK Community Page for other SPDK communications channels. 5. Copy the DPDK application binary to your target, then run the application as follows (assuming the platform has four memory channels per processor socket, and that cores 0-3 are present and are to be used for running the application): 7. -r <number of ranks> Set the number of memory ranks (auto-detected by default). Inline Functions 70. 4 KNI Traffic Flow Fig. 2 Hierarchical Scheduler Block Internal . Compiling the Application 3. Locking memory pages 70. 1 channel CPU到内存的通路是channel，每个channel对应一个CPU的内存控制器，每个channel可以配有多个DIMM。 双通道：CPU外核或北桥有两个内存控制器，每个控制器控制一个内存通道。理论上内存带宽 Each channel has a bandwidth limit, meaning that if all memory access operations are done on the first channel only, there is a potential bottleneck. Locks and Atomic Operations 47. This Jan 9, 2020 · Our popular series about Vector Packet Processing continues. --iova-mode <pa|va> Force 1 Introduction The Data Plane Development Kit (DPDK), has become the de facto standard on which packet processing applications and other packet processing frameworks are based. Therefore, you need to recompile and enable the DPDKstack component. See the DPDK Getting Started Guide for more information on these options. 15. Basic Multi-process Example The examples/simple_mp folder contains a basic example application that demonstrates how two DPDK processes can work together to share information using queues and memory pools. show port 4. Mar 7, 2019 · Please use the issue tracker only for reporting suspected issues. The parameter is a comma-separated list of values. Ensure that each memory channel has at least one memory DIMM inserted, and that the 7. At this point, the DPDK services 16. Locks and Atomic Operations 66. Memory Pool Library A memory pool is an allocator of a fixed-sized object. You can check the memory configuration using dmidecode as follows: Got feedback from a guy working on HPC with DPDK and he told me that with dpdk mem-test (don't know where to find it) I should be doing 16GB/s with DDR4 (2666) per channel. This library is used by the Mbuf Library and the 7. 3. start 4. It should match the number of memory channels on that setup. 说明 这一篇文章主要是对DPDK的EAL (Environment Abstraction Layer)中内存管理和分配的解析，这是DPDK中ring, mempool, mbuf等的基础。 一，DPDK的 内存 模式 DPDK存在两种 内存模式: 1, legacy mode : 这一种为 静态内存 模式，即在初始化过程就根据配置分配所有的内存，并且这些内存页在application结束之前 不会归还给OS Get the number of memory channels. 08 with DPDK version 16. You can check the memory configuration using dmidecode as follows: Definition: rte_log. This library is used by the Mbuf Library and the Environment 4. Sources: Memory-related options -n, --memory-channels <number of channels> Set the number of memory channels to use. For additional and more general information, please refer to the Intel® 64 and IA-32 Architectures Optimization Reference Manual which is a valuable reference to writing efficient code. EAL options: -c COREMASK : A hexadecimal bitmask of cores to run on -n NUM : Number of memory channels -v : Display version information on startup -d LIB. 6. May 12, 2025 · Memory pools implement several optimization techniques: The function optimize_object_size() calculates the optimal size by adding padding to ensure objects are distributed across memory channels and ranks based on system memory configuration. The specifics of both are detailed below. Ensure that both bonded interfaces are from NICs on the same NUMA node. 2 Packet Flow via mbufs in the DPDK KNI Fig. Lower Packet Latency 66. 0-53-generic Cores set to 65. Inline Functions 47. An mbuf contains a field indicating the pool that it originated from. This memory pool allocator is described in Memory Pool Library. Lower Packet Latency 70. dpdk从使用到驱动. For example: --socket-mem 1024,2048 This will allocate 1 gigabyte of memory on socket 0, and 2048 megabytes of 35. Buffers Stored in Memory Pools The Buffer Manager uses the Memory Pool Library to allocate buffers. 18. Testpmd Command-line Options 3. While previous articles have concentrated on outlining general concepts behind memory management in DPDK, giving an in-depth overview of various input-output virtual address (IOVA) related options, and describing memory related features available in DPDK 17. This May 17, 2020 · 1 前置知识点学习（了解） 从CPU到实际的存储节点，依据层级划分：Channel > DIMM > Rank > Chip > Bank > Row /Column 1. This memory is exposed to DPDK service layers such as the Mempool Library. When calling rte_pktmbuf_free (m), the mbuf returns to its original pool. It provides some other optional services, like a per-core object cache, and an alignment helper to ensure that objects are padded to spread them equally on all RAM channels, ranks, and so on. Ensure that memory channels are populated evenly to maximize bandwidth. The ``vswitch::dpdk::memory_channels`` parmeter now requires an integer Copy the DPDK application binary to your target, then run the application as follows (assuming the platform has four memory channels per processor socket, and that cores 0-3 are present and are to be used for running the application): 6. Note: this has one of the most direct effects on performance. While DPDK, and high-performance packet processing frameworks, have taken the concept of “zero-copy” packet processing to heart, there are scenarios in real-world applications where packet copies are necessary, and 2. Objects owned by a mempool should never be added in another mempool On application start-up in a primary or standalone process, the DPDK records to memory-mapped files the details of the memory configuration it is using - hugepages in use, the virtual addresses they are mapped at, the number of memory channels present, etc. Locks and Atomic Operations 70. Coding Considerations 66. 2. Efficient packet processing relies on ensuring that packets are readily accessible in the hardware cache. This is done automatically by the DPDK application at startup, if no -m or --numa-mem parameter is passed to it when run. Memory management — Allocates pools of objects in memory created in huge page memory space, uses a ring to store free objects, and spreads objects evenly across DRAM channels to optimize access speed. By default, the Mempool Library spreads the addresses of objects among memory channels. There are might be some corner cases, but those are quite rare and could be easily "fixed" not only Feb 28, 2022 · This article steps you through getting started with the Data Plane Development Kit (DPDK), including building and testing a sample application, l2fwd. --in-memory Do not create any shared data structures and run entirely in memory. Network Packet Buffer Management (librte_mbuf) To optimize total memory bandwidth, the physical addressing is often set up to automatically interleave between channels. Implies --no-shconf and (if applicable) --huge-unlink. Since most motherboards support dual or quad memory channel, -n 4 will work for most systems. This Copy the DPDK application binary to your target, then run the application as follows (assuming the platform has four memory channels per processor socket, and that cores 0-3 are present and are to be used for running the application): Compiling DPDKStack Ceph dpdkstack is not compiled by default. Lower Packet Latency 65. A memory pool is an allocator of fixed-size object. For example: --socket-mem 1024,2048 This will allocate 1 gigabyte of memory on socket 0, and 2048 megabytes of Thanks for your detailed reply, I just want to clear myself on Number of Memory Channels, These Memory channels are between CPU and Hugepages (RAM) or HugePages (RAM) and NIC (multi channel DMA) or both ? Thanks On Thu, Jun 20, 2013 at 8:43 PM, Stephen Hemminger < Post by Stephen Hemminger On Thu, 20 Jun 2013 16:20:35 +0500 Post by Muhammad Ali This compiles and runs the DPDK helloworld example, binding it to logical core 0 and using 2 memory channels. Locking memory pages 47. Branch Prediction 47. Atomic Operations: Use C11 Atomic Builtins 65. 2. Question and answering If you have any questions or want to use some special features, please submit an issue or a pull request on openeuler-docker-images ⁠. You can check the memory configuration using dmidecode as follows: 1. The main goal of the DPDK is to provide a simple, complete framework for fast packet processing in data plane applications. 3. 19. This 2. 8 LTS. 04. If more memory is requested by explicitly passing a -m or --numa-mem value, the application fails. Testpmd Runtime Functions 4. Running the Application To run the application, start simple_mp binary in one terminal, passing at least two cores in the corelist: 8. For example: --socket-mem 1024,2048 This will allocate 1 gigabyte of memory on socket 0, and 2048 megabytes of Nov 3, 2020 · Memory Access Address Alignment 在内存中存取一个变量最高效的方式是将其放在一个可以被它的长度整除的地址上。 (void *)&variable % sizeof (variable) == 0 所谓的按某个长度对齐就是这个意思。 GCC 编译器会自动帮我们处理这些事情。比较特殊的方式是将一个大型的结构体，或者静态数组按64byte的方式对齐： int 一、mempool的概念 DPDK的官方文档对mempool介绍如引用所示。 A memory pool is an allocator of a fixed-sized object. 10. 1 Components of a DPDK KNI Application Fig. The optimal memory size for each DIMM is at least 8, 16, or 32 GB, utilizing ECC modules. 6. Coding Considerations 70. Setting the Target CPU Type 48. Memory-related options -n <number of channels> Set the number of memory channels to use. Contribute to The-Dire/dpdk-by-example development by creating an account on GitHub. This library is used by the Mbuf Library and the Apr 26, 2022 · 用过 dpdk 的同学都知道，在 EAL 参数项中有两个参数 -n 和 -r，分别用于指定 内存 channel 数和 rank 数，这两个参数会影响 mbuf 的大小，dpdk 会根据这两个参数的值和用户指定的 mbuf 大小来确定一个更优的 mbuf 大小。 Aug 21, 2019 · Memory Pools DPDK also has a memory pool manager that is widely used throughout DPDK to manage large pools of objects of fixed size. Distribution Across Memory Channels 70. I think interleaving in 4 ways will also include 2 way interleaving. This 26. Distribution Across Memory Channels 65. However, the 7. Display Functions 4. Additionally, configure PCIe settings to enable maximum throughput between the processor and network cards. Memory & CPU management, with Hugepages, vlib, dual-loop, polling, IRQ, DPDK & more explained! 8. Profiling on x86 7. Communication Between lcores 70. This is so that writing to memory sequentially automatically utilizes all available channels. In the DPDK initialization phase, it uses a large space to form a memory pool, which is an object allocator with fix size (storing packets entities require memory alignment to ensure that the object in memory allocated in different memory channels). EAL Command-line Options ¶ The following are the EAL command-line options that can be used in conjunction with the testpmd, or any other DPDK application. 1 Complex Packet Processing Pipeline with QoS Support Fig. In the DPDK, it is identified by name and uses a ring to store free objects. Mempool Library ¶ A memory pool is an allocator of a fixed-sized object. A single or dual processor and PCH chip, except for System on Chip (SoC) cases DRAM memory size and frequency (normally single DIMM per channel) Specific Intel Network Interface Cards (NICs) BIOS settings noting those that updated from the basic settings DPDK build configuration settings, and commands used for tests Nov 18, 2011 · chan_info->priv_info = (void *)NULL; chan_info->status = CHANNEL_MGR_CHANNEL_DISCONNECTED; chan_info->type = CHANNEL_TYPE_JSON; fifo_path (chan_info->channel_path, sizeof (chan_info->channel_path)); if (open_host_channel (chan_info) < 0) { RTE_LOG (ERR, CHANNEL_MANAGER, "Could not open host channel: " "'%s'\n", chan_info->channel_path); return 10. Overview ¶ This section gives a global overview of the architecture of Data Plane Development Kit (DPDK).