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diff --git a/src/spdk/dpdk/doc/guides/linux_gsg/nic_perf_intel_platform.rst b/src/spdk/dpdk/doc/guides/linux_gsg/nic_perf_intel_platform.rst new file mode 100644 index 000000000..1dabbce24 --- /dev/null +++ b/src/spdk/dpdk/doc/guides/linux_gsg/nic_perf_intel_platform.rst @@ -0,0 +1,188 @@ +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. + + +Hardware and Memory Requirements +-------------------------------- + +For best performance use an Intel Xeon class server system such as Ivy Bridge, Haswell or newer. + +Ensure that each memory channel has at least one memory DIMM inserted, and that the memory size for each is at least 4GB. +**Note**: this has one of the most direct effects on performance. + +You can check the memory configuration using ``dmidecode`` as follows:: + + dmidecode -t memory | grep Locator + + Locator: DIMM_A1 + Bank Locator: NODE 1 + Locator: DIMM_A2 + Bank Locator: NODE 1 + Locator: DIMM_B1 + Bank Locator: NODE 1 + Locator: DIMM_B2 + Bank Locator: NODE 1 + ... + Locator: DIMM_G1 + Bank Locator: NODE 2 + Locator: DIMM_G2 + Bank Locator: NODE 2 + Locator: DIMM_H1 + Bank Locator: NODE 2 + Locator: DIMM_H2 + Bank Locator: NODE 2 + +The sample output above shows a total of 8 channels, from ``A`` to ``H``, where each channel has 2 DIMMs. + +You can also use ``dmidecode`` to determine the memory frequency:: + + dmidecode -t memory | grep Speed + + Speed: 2133 MHz + Configured Clock Speed: 2134 MHz + Speed: Unknown + Configured Clock Speed: Unknown + Speed: 2133 MHz + Configured Clock Speed: 2134 MHz + Speed: Unknown + ... + Speed: 2133 MHz + Configured Clock Speed: 2134 MHz + Speed: Unknown + Configured Clock Speed: Unknown + Speed: 2133 MHz + Configured Clock Speed: 2134 MHz + Speed: Unknown + Configured Clock Speed: Unknown + +The output shows a speed of 2133 MHz (DDR4) and Unknown (not existing). +This aligns with the previous output which showed that each channel has one memory bar. + + +Network Interface Card Requirements +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Use a `DPDK supported <https://core.dpdk.org/supported/>`_ high end NIC such as the Intel XL710 40GbE. + +Make sure each NIC has been flashed the latest version of NVM/firmware. + +Use PCIe Gen3 slots, such as Gen3 ``x8`` or Gen3 ``x16`` because PCIe Gen2 slots don't provide enough bandwidth +for 2 x 10GbE and above. +You can use ``lspci`` to check the speed of a PCI slot using something like the following:: + + lspci -s 03:00.1 -vv | grep LnkSta + + LnkSta: Speed 8GT/s, Width x8, TrErr- Train- SlotClk+ DLActive- ... + LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete+ ... + +When inserting NICs into PCI slots always check the caption, such as CPU0 or CPU1 to indicate which socket it is connected to. + +Care should be take with NUMA. +If you are using 2 or more ports from different NICs, it is best to ensure that these NICs are on the same CPU socket. +An example of how to determine this is shown further below. + + +BIOS Settings +~~~~~~~~~~~~~ + +The following are some recommendations on BIOS settings. Different platforms will have different BIOS naming +so the following is mainly for reference: + +#. Establish the steady state for the system, consider reviewing BIOS settings desired for best performance characteristic e.g. optimize for performance or energy efficiency. + +#. Match the BIOS settings to the needs of the application you are testing. + +#. Typically, **Performance** as the CPU Power and Performance policy is a reasonable starting point. + +#. Consider using Turbo Boost to increase the frequency on cores. + +#. Disable all virtualization options when you test the physical function of the NIC, and turn on VT-d if you wants to use VFIO. + + +Linux boot command line +~~~~~~~~~~~~~~~~~~~~~~~ + +The following are some recommendations on GRUB boot settings: + +#. Use the default grub file as a starting point. + +#. Reserve 1G huge pages via grub configurations. For example to reserve 8 huge pages of 1G size:: + + default_hugepagesz=1G hugepagesz=1G hugepages=8 + +#. Isolate CPU cores which will be used for DPDK. For example:: + + isolcpus=2,3,4,5,6,7,8 + +#. If it wants to use VFIO, use the following additional grub parameters:: + + iommu=pt intel_iommu=on + + +Configurations before running DPDK +---------------------------------- + +1. Build the DPDK target and reserve huge pages. + See the earlier section on :ref:`linux_gsg_hugepages` for more details. + + The following shell commands may help with building and configuration: + + .. code-block:: console + + # Build DPDK target. + cd dpdk_folder + make install T=x86_64-native-linux-gcc -j + + # Get the hugepage size. + awk '/Hugepagesize/ {print $2}' /proc/meminfo + + # Get the total huge page numbers. + awk '/HugePages_Total/ {print $2} ' /proc/meminfo + + # Unmount the hugepages. + umount `awk '/hugetlbfs/ {print $2}' /proc/mounts` + + # Create the hugepage mount folder. + mkdir -p /mnt/huge + + # Mount to the specific folder. + mount -t hugetlbfs nodev /mnt/huge + +2. Check the CPU layout using the DPDK ``cpu_layout`` utility: + + .. code-block:: console + + cd dpdk_folder + + usertools/cpu_layout.py + + Or run ``lscpu`` to check the cores on each socket. + +3. Check your NIC id and related socket id: + + .. code-block:: console + + # List all the NICs with PCI address and device IDs. + lspci -nn | grep Eth + + For example suppose your output was as follows:: + + 82:00.0 Ethernet [0200]: Intel XL710 for 40GbE QSFP+ [8086:1583] + 82:00.1 Ethernet [0200]: Intel XL710 for 40GbE QSFP+ [8086:1583] + 85:00.0 Ethernet [0200]: Intel XL710 for 40GbE QSFP+ [8086:1583] + 85:00.1 Ethernet [0200]: Intel XL710 for 40GbE QSFP+ [8086:1583] + + Check the PCI device related numa node id: + + .. code-block:: console + + cat /sys/bus/pci/devices/0000\:xx\:00.x/numa_node + + Usually ``0x:00.x`` is on socket 0 and ``8x:00.x`` is on socket 1. + **Note**: To get the best performance, ensure that the core and NICs are in the same socket. + In the example above ``85:00.0`` is on socket 1 and should be used by cores on socket 1 for the best performance. + +4. Check which kernel drivers needs to be loaded and whether there is a need to unbind the network ports from their kernel drivers. +More details about DPDK setup and Linux kernel requirements see :ref:`linux_gsg_compiling_dpdk` and :ref:`linux_gsg_linux_drivers`. |