Signed-off-by: Stephen Finucane <step...@that.guru> --- INSTALL.DPDK-ADVANCED.md | 898 -------------------------------------------- INSTALL.DPDK-ADVANCED.rst | 938 ++++++++++++++++++++++++++++++++++++++++++++++ INSTALL.DPDK.rst | 10 +- Makefile.am | 2 +- 4 files changed, 944 insertions(+), 904 deletions(-) delete mode 100644 INSTALL.DPDK-ADVANCED.md create mode 100644 INSTALL.DPDK-ADVANCED.rst
diff --git a/INSTALL.DPDK-ADVANCED.md b/INSTALL.DPDK-ADVANCED.md deleted file mode 100644 index 0d6bcfa..0000000 --- a/INSTALL.DPDK-ADVANCED.md +++ /dev/null @@ -1,898 +0,0 @@ -OVS DPDK ADVANCED INSTALL GUIDE -=============================== - -## Contents - -1. [Overview](#overview) -2. [Building Shared Library](#build) -3. [System configuration](#sysconf) -4. [Performance Tuning](#perftune) -5. [OVS Testcases](#ovstc) -6. [Vhost Walkthrough](#vhost) -7. [QOS](#qos) -8. [Rate Limiting](#rl) -9. [Flow Control](#fc) -10. [Pdump](#pdump) -11. [Jumbo Frames](#jumbo) -12. [Vsperf](#vsperf) - -## <a name="overview"></a> 1. Overview - -The Advanced Install Guide explains how to improve OVS performance using -DPDK datapath. This guide also provides information on tuning, system configuration, -troubleshooting, static code analysis and testcases. - -## <a name="build"></a> 2. Building Shared Library - -DPDK can be built as static or shared library and shall be linked by applications -using DPDK datapath. The section lists steps to build shared library and dynamically -link DPDK against OVS. - -Note: Minor performance loss is seen with OVS when using shared DPDK library as -compared to static library. - -Check section [INSTALL DPDK], [INSTALL OVS] of INSTALL.DPDK on download instructions -for DPDK and OVS. - - * Configure the DPDK library - - Set `CONFIG_RTE_BUILD_SHARED_LIB=y` in `config/common_base` - to generate shared DPDK library - - - * Build and install DPDK - - For Default install (without IVSHMEM), set `export DPDK_TARGET=x86_64-native-linuxapp-gcc` - For IVSHMEM case, set `export DPDK_TARGET=x86_64-ivshmem-linuxapp-gcc` - - ``` - export DPDK_DIR=/usr/src/dpdk-16.07 - export DPDK_BUILD=$DPDK_DIR/$DPDK_TARGET - make install T=$DPDK_TARGET DESTDIR=install - ``` - - * Build, Install and Setup OVS. - - Export the DPDK shared library location and setup OVS as listed in - section 3.3 of INSTALL.DPDK. - - `export LD_LIBRARY_PATH=$DPDK_DIR/x86_64-native-linuxapp-gcc/lib` - -## <a name="sysconf"></a> 3. System Configuration - -To achieve optimal OVS performance, the system can be configured and that includes -BIOS tweaks, Grub cmdline additions, better understanding of NUMA nodes and -apt selection of PCIe slots for NIC placement. - -### 3.1 Recommended BIOS settings - - ``` - | Settings | values | comments - |---------------------------|-----------|----------- - | C3 power state | Disabled | - - | C6 power state | Disabled | - - | MLC Streamer | Enabled | - - | MLC Spacial prefetcher | Enabled | - - | DCU Data prefetcher | Enabled | - - | DCA | Enabled | - - | CPU power and performance | Performance - - | Memory RAS and perf | | - - config-> NUMA optimized | Enabled | - - ``` - -### 3.2 PCIe Slot Selection - -The fastpath performance also depends on factors like the NIC placement, -Channel speeds between PCIe slot and CPU, proximity of PCIe slot to the CPU -cores running DPDK application. Listed below are the steps to identify -right PCIe slot. - -- Retrieve host details using cmd `dmidecode -t baseboard | grep "Product Name"` -- Download the technical specification for Product listed eg: S2600WT2. -- Check the Product Architecture Overview on the Riser slot placement, - CPU sharing info and also PCIe channel speeds. - - example: On S2600WT, CPU1 and CPU2 share Riser Slot 1 with Channel speed between - CPU1 and Riser Slot1 at 32GB/s, CPU2 and Riser Slot1 at 16GB/s. Running DPDK app - on CPU1 cores and NIC inserted in to Riser card Slots will optimize OVS performance - in this case. - -- Check the Riser Card #1 - Root Port mapping information, on the available slots - and individual bus speeds. In S2600WT slot 1, slot 2 has high bus speeds and are - potential slots for NIC placement. - -### 3.3 Advanced Hugepage setup - - Allocate and mount 1G Huge pages: - - - For persistent allocation of huge pages, add the following options to the kernel bootline - - Add `default_hugepagesz=1GB hugepagesz=1G hugepages=N` - - For platforms supporting multiple huge page sizes, Add options - - `default_hugepagesz=<size> hugepagesz=<size> hugepages=N` - where 'N' = Number of huge pages requested, 'size' = huge page size, - optional suffix [kKmMgG] - - - For run-time allocation of huge pages - - `echo N > /sys/devices/system/node/nodeX/hugepages/hugepages-1048576kB/nr_hugepages` - where 'N' = Number of huge pages requested, 'X' = NUMA Node - - Note: For run-time allocation of 1G huge pages, Contiguous Memory Allocator(CONFIG_CMA) - has to be supported by kernel, check your Linux distro. - - - Mount huge pages - - `mount -t hugetlbfs -o pagesize=1G none /dev/hugepages` - - Note: Mount hugepages if not already mounted by default. - -### 3.4 Enable Hyperthreading - - Requires BIOS changes - - With HT/SMT enabled, A Physical core appears as two logical cores. - SMT can be utilized to spawn worker threads on logical cores of the same - physical core there by saving additional cores. - - With DPDK, When pinning pmd threads to logical cores, care must be taken - to set the correct bits in the pmd-cpu-mask to ensure that the pmd threads are - pinned to SMT siblings. - - Example System configuration: - Dual socket Machine, 2x 10 core processors, HT enabled, 40 logical cores - - To use two logical cores which share the same physical core for pmd threads, - the following command can be used to identify a pair of logical cores. - - `cat /sys/devices/system/cpu/cpuN/topology/thread_siblings_list`, where N is the - logical core number. - - In this example, it would show that cores 1 and 21 share the same physical core. - The pmd-cpu-mask to enable two pmd threads running on these two logical cores - (one physical core) is. - - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=100002` - -### 3.5 Isolate cores - - 'isolcpus' option can be used to isolate cores from the linux scheduler. - The isolated cores can then be used to dedicatedly run HPC applications/threads. - This helps in better application performance due to zero context switching and - minimal cache thrashing. To run platform logic on core 0 and isolate cores - between 1 and 19 from scheduler, Add `isolcpus=1-19` to GRUB cmdline. - - Note: It has been verified that core isolation has minimal advantage due to - mature Linux scheduler in some circumstances. - -### 3.6 NUMA/Cluster on Die - - Ideally inter NUMA datapaths should be avoided where possible as packets - will go across QPI and there may be a slight performance penalty when - compared with intra NUMA datapaths. On Intel Xeon Processor E5 v3, - Cluster On Die is introduced on models that have 10 cores or more. - This makes it possible to logically split a socket into two NUMA regions - and again it is preferred where possible to keep critical datapaths - within the one cluster. - - It is good practice to ensure that threads that are in the datapath are - pinned to cores in the same NUMA area. e.g. pmd threads and QEMU vCPUs - responsible for forwarding. If DPDK is built with - CONFIG_RTE_LIBRTE_VHOST_NUMA=y, vHost User ports automatically - detect the NUMA socket of the QEMU vCPUs and will be serviced by a PMD - from the same node provided a core on this node is enabled in the - pmd-cpu-mask. libnuma packages are required for this feature. - -### 3.7 Compiler Optimizations - - The default compiler optimization level is '-O2'. Changing this to - more aggressive compiler optimization such as '-O3 -march=native' - with gcc(verified on 5.3.1) can produce performance gains though not - siginificant. '-march=native' will produce optimized code on local machine - and should be used when SW compilation is done on Testbed. - -## <a name="perftune"></a> 4. Performance Tuning - -### 4.1 Affinity - -For superior performance, DPDK pmd threads and Qemu vCPU threads -needs to be affinitized accordingly. - - * PMD thread Affinity - - A poll mode driver (pmd) thread handles the I/O of all DPDK - interfaces assigned to it. A pmd thread shall poll the ports - for incoming packets, switch the packets and send to tx port. - pmd thread is CPU bound, and needs to be affinitized to isolated - cores for optimum performance. - - By setting a bit in the mask, a pmd thread is created and pinned - to the corresponding CPU core. e.g. to run a pmd thread on core 2 - - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=4` - - Note: pmd thread on a NUMA node is only created if there is - at least one DPDK interface from that NUMA node added to OVS. - - * Qemu vCPU thread Affinity - - A VM performing simple packet forwarding or running complex packet - pipelines has to ensure that the vCPU threads performing the work has - as much CPU occupancy as possible. - - Example: On a multicore VM, multiple QEMU vCPU threads shall be spawned. - when the DPDK 'testpmd' application that does packet forwarding - is invoked, 'taskset' cmd should be used to affinitize the vCPU threads - to the dedicated isolated cores on the host system. - -### 4.2 Multiple poll mode driver threads - - With pmd multi-threading support, OVS creates one pmd thread - for each NUMA node by default. However, it can be seen that in cases - where there are multiple ports/rxq's producing traffic, performance - can be improved by creating multiple pmd threads running on separate - cores. These pmd threads can then share the workload by each being - responsible for different ports/rxq's. Assignment of ports/rxq's to - pmd threads is done automatically. - - A set bit in the mask means a pmd thread is created and pinned - to the corresponding CPU core. e.g. to run pmd threads on core 1 and 2 - - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=6` - - For example, when using dpdk and dpdkvhostuser ports in a bi-directional - VM loopback as shown below, spreading the workload over 2 or 4 pmd - threads shows significant improvements as there will be more total CPU - occupancy available. - - NIC port0 <-> OVS <-> VM <-> OVS <-> NIC port 1 - -### 4.3 DPDK physical port Rx Queues - - `ovs-vsctl set Interface <DPDK interface> options:n_rxq=<integer>` - - The command above sets the number of rx queues for DPDK physical interface. - The rx queues are assigned to pmd threads on the same NUMA node in a - round-robin fashion. - -### 4.4 DPDK Physical Port Queue Sizes - `ovs-vsctl set Interface dpdk0 options:n_rxq_desc=<integer>` - `ovs-vsctl set Interface dpdk0 options:n_txq_desc=<integer>` - - The command above sets the number of rx/tx descriptors that the NIC - associated with dpdk0 will be initialised with. - - Different 'n_rxq_desc' and 'n_txq_desc' configurations yield different - benefits in terms of throughput and latency for different scenarios. - Generally, smaller queue sizes can have a positive impact for latency at the - expense of throughput. The opposite is often true for larger queue sizes. - Note: increasing the number of rx descriptors eg. to 4096 may have a - negative impact on performance due to the fact that non-vectorised DPDK rx - functions may be used. This is dependant on the driver in use, but is true - for the commonly used i40e and ixgbe DPDK drivers. - -### 4.5 Exact Match Cache - - Each pmd thread contains one EMC. After initial flow setup in the - datapath, the EMC contains a single table and provides the lowest level - (fastest) switching for DPDK ports. If there is a miss in the EMC then - the next level where switching will occur is the datapath classifier. - Missing in the EMC and looking up in the datapath classifier incurs a - significant performance penalty. If lookup misses occur in the EMC - because it is too small to handle the number of flows, its size can - be increased. The EMC size can be modified by editing the define - EM_FLOW_HASH_SHIFT in lib/dpif-netdev.c. - - As mentioned above an EMC is per pmd thread. So an alternative way of - increasing the aggregate amount of possible flow entries in EMC and - avoiding datapath classifier lookups is to have multiple pmd threads - running. This can be done as described in section 4.2. - -### 4.6 Rx Mergeable buffers - - Rx Mergeable buffers is a virtio feature that allows chaining of multiple - virtio descriptors to handle large packet sizes. As such, large packets - are handled by reserving and chaining multiple free descriptors - together. Mergeable buffer support is negotiated between the virtio - driver and virtio device and is supported by the DPDK vhost library. - This behavior is typically supported and enabled by default, however - in the case where the user knows that rx mergeable buffers are not needed - i.e. jumbo frames are not needed, it can be forced off by adding - mrg_rxbuf=off to the QEMU command line options. By not reserving multiple - chains of descriptors it will make more individual virtio descriptors - available for rx to the guest using dpdkvhost ports and this can improve - performance. - -## <a name="ovstc"></a> 5. OVS Testcases -### 5.1 PHY-VM-PHY [VHOST LOOPBACK] - -The section 5.2 in INSTALL.DPDK guide lists steps for PVP loopback testcase -and packet forwarding using DPDK testpmd application in the Guest VM. -For users wanting to do packet forwarding using kernel stack below are the steps. - - ``` - ifconfig eth1 1.1.1.2/24 - ifconfig eth2 1.1.2.2/24 - systemctl stop firewalld.service - systemctl stop iptables.service - sysctl -w net.ipv4.ip_forward=1 - sysctl -w net.ipv4.conf.all.rp_filter=0 - sysctl -w net.ipv4.conf.eth1.rp_filter=0 - sysctl -w net.ipv4.conf.eth2.rp_filter=0 - route add -net 1.1.2.0/24 eth2 - route add -net 1.1.1.0/24 eth1 - arp -s 1.1.2.99 DE:AD:BE:EF:CA:FE - arp -s 1.1.1.99 DE:AD:BE:EF:CA:EE - ``` - -### 5.2 PHY-VM-PHY [IVSHMEM] - - The steps (1-5) in 3.3 section of INSTALL.DPDK guide will create & initialize DB, - start vswitchd and add dpdk devices to bridge br0. - - 1. Add DPDK ring port to the bridge - - ``` - ovs-vsctl add-port br0 dpdkr0 -- set Interface dpdkr0 type=dpdkr - ``` - - 2. Build modified Qemu (Qemu-2.2.1 + ivshmem-qemu-2.2.1.patch) - - ``` - cd /usr/src/ - wget http://wiki.qemu.org/download/qemu-2.2.1.tar.bz2 - tar -jxvf qemu-2.2.1.tar.bz2 - cd /usr/src/qemu-2.2.1 - wget https://raw.githubusercontent.com/netgroup-polito/un-orchestrator/master/orchestrator/compute_controller/plugins/kvm-libvirt/patches/ivshmem-qemu-2.2.1.patch - patch -p1 < ivshmem-qemu-2.2.1.patch - ./configure --target-list=x86_64-softmmu --enable-debug --extra-cflags='-g' - make -j 4 - ``` - - 3. Generate Qemu commandline - - ``` - mkdir -p /usr/src/cmdline_generator - cd /usr/src/cmdline_generator - wget https://raw.githubusercontent.com/netgroup-polito/un-orchestrator/master/orchestrator/compute_controller/plugins/kvm-libvirt/cmdline_generator/cmdline_generator.c - wget https://raw.githubusercontent.com/netgroup-polito/un-orchestrator/master/orchestrator/compute_controller/plugins/kvm-libvirt/cmdline_generator/Makefile - export RTE_SDK=/usr/src/dpdk-16.07 - export RTE_TARGET=x86_64-ivshmem-linuxapp-gcc - make - ./build/cmdline_generator -m -p dpdkr0 XXX - cmdline=`cat OVSMEMPOOL` - ``` - - 4. start Guest VM - - ``` - export VM_NAME=ivshmem-vm - export QCOW2_IMAGE=/root/CentOS7_x86_64.qcow2 - export QEMU_BIN=/usr/src/qemu-2.2.1/x86_64-softmmu/qemu-system-x86_64 - - taskset 0x20 $QEMU_BIN -cpu host -smp 2,cores=2 -hda $QCOW2_IMAGE -m 4096 --enable-kvm -name $VM_NAME -nographic -vnc :2 -pidfile /tmp/vm1.pid $cmdline - ``` - - 5. Running sample "dpdk ring" app in VM - - ``` - echo 1024 > /proc/sys/vm/nr_hugepages - mount -t hugetlbfs nodev /dev/hugepages (if not already mounted) - - # Build the DPDK ring application in the VM - export RTE_SDK=/root/dpdk-16.07 - export RTE_TARGET=x86_64-ivshmem-linuxapp-gcc - make - - # Run dpdkring application - ./build/dpdkr -c 1 -n 4 -- -n 0 - where "-n 0" refers to ring '0' i.e dpdkr0 - ``` - -### 5.3 PHY-VM-PHY [VHOST MULTIQUEUE] - - The steps (1-5) in 3.3 section of [INSTALL DPDK] guide will create & initialize DB, - start vswitchd and add dpdk devices to bridge br0. - - 1. Configure PMD and RXQs. For example set no. of dpdk port rx queues to atleast 2. - The number of rx queues at vhost-user interface gets automatically configured after - virtio device connection and doesn't need manual configuration. - - ``` - ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=c - ovs-vsctl set Interface dpdk0 options:n_rxq=2 - ovs-vsctl set Interface dpdk1 options:n_rxq=2 - ``` - - 2. Instantiate Guest VM using Qemu cmdline - - Guest Configuration - - ``` - | configuration | values | comments - |----------------------|--------|----------------- - | qemu version | 2.5.0 | - | qemu thread affinity |2 cores | taskset 0x30 - | memory | 4GB | - - | cores | 2 | - - | Qcow2 image |Fedora22| - - | multiqueue | on | - - ``` - - Instantiate Guest - - ``` - export VM_NAME=vhost-vm - export GUEST_MEM=4096M - export QCOW2_IMAGE=/root/Fedora22_x86_64.qcow2 - export VHOST_SOCK_DIR=/usr/local/var/run/openvswitch - - taskset 0x30 qemu-system-x86_64 -cpu host -smp 2,cores=2 -drive file=$QCOW2_IMAGE -m 4096M --enable-kvm -name $VM_NAME -nographic -object memory-backend-file,id=mem,size=$GUEST_MEM,mem-path=/dev/hugepages,share=on -numa node,memdev=mem -mem-prealloc -chardev socket,id=char1,path=$VHOST_SOCK_DIR/dpdkvhostuser0 -netdev type=vhost-user,id=mynet1,chardev=char1,vhostforce,queues=2 -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1,mq=on,vectors=6 -chardev socket,id=char2,path=$VHOST_SOCK_DIR/dpdkvhostuser1 -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce,queues=2 -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2,mq=on,vectors=6 - ``` - - Note: Queue value above should match the queues configured in OVS, The vector value - should be set to 'no. of queues x 2 + 2'. - - 3. Guest interface configuration - - Assuming there are 2 interfaces in the guest named eth0, eth1 check the channel - configuration and set the number of combined channels to 2 for virtio devices. - More information can be found in [Vhost walkthrough] section. - - ``` - ethtool -l eth0 - ethtool -L eth0 combined 2 - ethtool -L eth1 combined 2 - ``` - - 4. Kernel Packet forwarding - - Configure IP and enable interfaces - - ``` - ifconfig eth0 5.5.5.1/24 up - ifconfig eth1 90.90.90.1/24 up - ``` - - Configure IP forwarding and add route entries - - ``` - sysctl -w net.ipv4.ip_forward=1 - sysctl -w net.ipv4.conf.all.rp_filter=0 - sysctl -w net.ipv4.conf.eth0.rp_filter=0 - sysctl -w net.ipv4.conf.eth1.rp_filter=0 - ip route add 2.1.1.0/24 dev eth1 - route add default gw 2.1.1.2 eth1 - route add default gw 90.90.90.90 eth1 - arp -s 90.90.90.90 DE:AD:BE:EF:CA:FE - arp -s 2.1.1.2 DE:AD:BE:EF:CA:FA - ``` - - Check traffic on multiple queues - - ``` - cat /proc/interrupts | grep virtio - ``` - -## <a name="vhost"></a> 6. Vhost Walkthrough - -Two types of vHost User ports are available in OVS: - -1. vhost-user (dpdkvhostuser ports) - -2. vhost-user-client (dpdkvhostuserclient ports) - -vHost User uses a client-server model. The server creates/manages/destroys the -vHost User sockets, and the client connects to the server. Depending on which -port type you use, dpdkvhostuser or dpdkvhostuserclient, a different -configuration of the client-server model is used. - -For vhost-user ports, OVS DPDK acts as the server and QEMU the client. -For vhost-user-client ports, OVS DPDK acts as the client and QEMU the server. - -### 6.1 vhost-user - - - Prerequisites: - - QEMU version >= 2.2 - - - Adding vhost-user ports to Switch - - Unlike DPDK ring ports, DPDK vhost-user ports can have arbitrary names, - except that forward and backward slashes are prohibited in the names. - - For vhost-user, the name of the port type is `dpdkvhostuser` - - ``` - ovs-vsctl add-port br0 vhost-user-1 -- set Interface vhost-user-1 - type=dpdkvhostuser - ``` - - This action creates a socket located at - `/usr/local/var/run/openvswitch/vhost-user-1`, which you must provide - to your VM on the QEMU command line. More instructions on this can be - found in the next section "Adding vhost-user ports to VM" - - Note: If you wish for the vhost-user sockets to be created in a - sub-directory of `/usr/local/var/run/openvswitch`, you may specify - this directory in the ovsdb like so: - - `./utilities/ovs-vsctl --no-wait \ - set Open_vSwitch . other_config:vhost-sock-dir=subdir` - - - Adding vhost-user ports to VM - - 1. Configure sockets - - Pass the following parameters to QEMU to attach a vhost-user device: - - ``` - -chardev socket,id=char1,path=/usr/local/var/run/openvswitch/vhost-user-1 - -netdev type=vhost-user,id=mynet1,chardev=char1,vhostforce - -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1 - ``` - - where vhost-user-1 is the name of the vhost-user port added - to the switch. - Repeat the above parameters for multiple devices, changing the - chardev path and id as necessary. Note that a separate and different - chardev path needs to be specified for each vhost-user device. For - example you have a second vhost-user port named 'vhost-user-2', you - append your QEMU command line with an additional set of parameters: - - ``` - -chardev socket,id=char2,path=/usr/local/var/run/openvswitch/vhost-user-2 - -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce - -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2 - ``` - - 2. Configure huge pages. - - QEMU must allocate the VM's memory on hugetlbfs. vhost-user ports access - a virtio-net device's virtual rings and packet buffers mapping the VM's - physical memory on hugetlbfs. To enable vhost-user ports to map the VM's - memory into their process address space, pass the following parameters - to QEMU: - - ``` - -object memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages, - share=on -numa node,memdev=mem -mem-prealloc - ``` - - 3. Enable multiqueue support(OPTIONAL) - - QEMU needs to be configured to use multiqueue. - The $q below is the number of queues. - The $v is the number of vectors, which is '$q x 2 + 2'. - - ``` - -chardev socket,id=char2,path=/usr/local/var/run/openvswitch/vhost-user-2 - -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce,queues=$q - -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2,mq=on,vectors=$v - ``` - - The vhost-user interface will be automatically reconfigured with required - number of rx and tx queues after connection of virtio device. - Manual configuration of `n_rxq` is not supported because OVS will work - properly only if `n_rxq` will match number of queues configured in QEMU. - - A least 2 PMDs should be configured for the vswitch when using multiqueue. - Using a single PMD will cause traffic to be enqueued to the same vhost - queue rather than being distributed among different vhost queues for a - vhost-user interface. - - If traffic destined for a VM configured with multiqueue arrives to the - vswitch via a physical DPDK port, then the number of rxqs should also be - set to at least 2 for that physical DPDK port. This is required to increase - the probability that a different PMD will handle the multiqueue - transmission to the guest using a different vhost queue. - - If one wishes to use multiple queues for an interface in the guest, the - driver in the guest operating system must be configured to do so. It is - recommended that the number of queues configured be equal to '$q'. - - For example, this can be done for the Linux kernel virtio-net driver with: - - ``` - ethtool -L <DEV> combined <$q> - ``` - where `-L`: Changes the numbers of channels of the specified network device - and `combined`: Changes the number of multi-purpose channels. - - - VM Configuration with libvirt - - * change the user/group, access control policty and restart libvirtd. - - - In `/etc/libvirt/qemu.conf` add/edit the following lines - - ``` - user = "root" - group = "root" - ``` - - - Disable SELinux or set to permissive mode - - `setenforce 0` - - - Restart the libvirtd process, For example, on Fedora - - `systemctl restart libvirtd.service` - - * Instantiate the VM - - - Copy the xml configuration from [Guest VM using libvirt] in to workspace. - - - Start the VM. - - `virsh create demovm.xml` - - - Connect to the guest console - - `virsh console demovm` - - * VM configuration - - The demovm xml configuration is aimed at achieving out of box performance - on VM. - - - The vcpus are pinned to the cores of the CPU socket 0 using vcpupin. - - - Configure NUMA cell and memory shared using memAccess='shared'. - - - Disable mrg_rxbuf='off'. - - Note: For information on libvirt and further tuning refer [libvirt]. - -### 6.2 vhost-user-client - - - Prerequisites: - - QEMU version >= 2.7 - - - Adding vhost-user-client ports to Switch - - ``` - ovs-vsctl add-port br0 vhost-client-1 -- set Interface vhost-client-1 - type=dpdkvhostuserclient options:vhost-server-path=/path/to/socket - ``` - - Unlike vhost-user ports, the name given to port does not govern the name of - the socket device. 'vhost-server-path' reflects the full path of the socket - that has been or will be created by QEMU for the given vHost User client - port. - - - Adding vhost-user-client ports to VM - - The same QEMU parameters as vhost-user ports described in section 6.1 can - be used, with one change necessary. One must append ',server' to the - 'chardev' arguments on the QEMU command line, to instruct QEMU to use vHost - server mode for a given interface, like so: - - ```` - -chardev socket,id=char0,path=/path/to/socket,server - ```` - - If the corresponding dpdkvhostuserclient port has not yet been configured - in OVS with vhost-server-path=/path/to/socket, QEMU will print a log - similar to the following: - - `QEMU waiting for connection on: disconnected:unix:/path/to/socket,server` - - QEMU will wait until the port is created sucessfully in OVS to boot the VM. - - One benefit of using this mode is the ability for vHost ports to - 'reconnect' in event of the switch crashing or being brought down. Once it - is brought back up, the vHost ports will reconnect automatically and normal - service will resume. - -### 6.3 DPDK backend inside VM - - Please note that additional configuration is required if you want to run - ovs-vswitchd with DPDK backend inside a QEMU virtual machine. Ovs-vswitchd - creates separate DPDK TX queues for each CPU core available. This operation - fails inside QEMU virtual machine because, by default, VirtIO NIC provided - to the guest is configured to support only single TX queue and single RX - queue. To change this behavior, you need to turn on 'mq' (multiqueue) - property of all virtio-net-pci devices emulated by QEMU and used by DPDK. - You may do it manually (by changing QEMU command line) or, if you use - Libvirt, by adding the following string: - - `<driver name='vhost' queues='N'/>` - - to <interface> sections of all network devices used by DPDK. Parameter 'N' - determines how many queues can be used by the guest.This may not work with - old versions of QEMU found in some distros and need Qemu version >= 2.2. - -## <a name="qos"></a> 7. QOS - -Here is an example on QOS usage. -Assuming you have a vhost-user port transmitting traffic consisting of -packets of size 64 bytes, the following command would limit the egress -transmission rate of the port to ~1,000,000 packets per second - -`ovs-vsctl set port vhost-user0 qos=@newqos -- --id=@newqos create qos -type=egress-policer other-config:cir=46000000 other-config:cbs=2048` - -To examine the QoS configuration of the port: - -`ovs-appctl -t ovs-vswitchd qos/show vhost-user0` - -To clear the QoS configuration from the port and ovsdb use the following: - -`ovs-vsctl destroy QoS vhost-user0 -- clear Port vhost-user0 qos` - -For more details regarding egress-policer parameters please refer to the -vswitch.xml. - -## <a name="rl"></a> 8. Rate Limiting - -Here is an example on Ingress Policing usage. -Assuming you have a vhost-user port receiving traffic consisting of -packets of size 64 bytes, the following command would limit the reception -rate of the port to ~1,000,000 packets per second: - -`ovs-vsctl set interface vhost-user0 ingress_policing_rate=368000 - ingress_policing_burst=1000` - -To examine the ingress policer configuration of the port: - -`ovs-vsctl list interface vhost-user0` - -To clear the ingress policer configuration from the port use the following: - -`ovs-vsctl set interface vhost-user0 ingress_policing_rate=0` - -For more details regarding ingress-policer see the vswitch.xml. - -## <a name="fc"></a> 9. Flow control. -Flow control can be enabled only on DPDK physical ports. -To enable flow control support at tx side while adding a port, add the -'tx-flow-ctrl' option to the 'ovs-vsctl add-port' as in the eg: below. - -``` -ovs-vsctl add-port br0 dpdk0 -- \ -set Interface dpdk0 type=dpdk options:tx-flow-ctrl=true -``` - -Similarly to enable rx flow control, - -``` -ovs-vsctl add-port br0 dpdk0 -- \ -set Interface dpdk0 type=dpdk options:rx-flow-ctrl=true -``` - -And to enable the flow control auto-negotiation, - -``` -ovs-vsctl add-port br0 dpdk0 -- \ -set Interface dpdk0 type=dpdk options:flow-ctrl-autoneg=true -``` - -To turn ON the tx flow control at run time(After the port is being added -to OVS), the command-line input will be, - -`ovs-vsctl set Interface dpdk0 options:tx-flow-ctrl=true` - -The flow control parameters can be turned off by setting 'false' to the -respective parameter. To disable the flow control at tx side, - -`ovs-vsctl set Interface dpdk0 options:tx-flow-ctrl=false` - -## <a name="pdump"></a> 10. Pdump - -Pdump allows you to listen on DPDK ports and view the traffic that is -passing on them. To use this utility, one must have libpcap installed -on the system. Furthermore, DPDK must be built with CONFIG_RTE_LIBRTE_PDUMP=y -and CONFIG_RTE_LIBRTE_PMD_PCAP=y. - -To use pdump, simply launch OVS as usual. Then, navigate to the 'app/pdump' -directory in DPDK, 'make' the application and run like so: - -``` -sudo ./build/app/dpdk-pdump -- ---pdump port=0,queue=0,rx-dev=/tmp/pkts.pcap ---server-socket-path=/usr/local/var/run/openvswitch -``` - -The above command captures traffic received on queue 0 of port 0 and stores -it in /tmp/pkts.pcap. Other combinations of port numbers, queues numbers and -pcap locations are of course also available to use. For example, to capture -all packets that traverse port 0 in a single pcap file: - -``` -sudo ./build/app/dpdk-pdump -- ---pdump 'port=0,queue=*,rx-dev=/tmp/pkts.pcap,tx-dev=/tmp/pkts.pcap' ---server-socket-path=/usr/local/var/run/openvswitch -``` - -'server-socket-path' must be set to the value of ovs_rundir() which typically -resolves to '/usr/local/var/run/openvswitch'. -More information on the pdump app and its usage can be found in the below link. - -http://dpdk.org/doc/guides/sample_app_ug/pdump.html - -Many tools are available to view the contents of the pcap file. Once example is -tcpdump. Issue the following command to view the contents of 'pkts.pcap': - -`tcpdump -r pkts.pcap` - -A performance decrease is expected when using a monitoring application like -the DPDK pdump app. - -## <a name="jumbo"></a> 11. Jumbo Frames - -By default, DPDK ports are configured with standard Ethernet MTU (1500B). To -enable Jumbo Frames support for a DPDK port, change the Interface's `mtu_request` -attribute to a sufficiently large value. - -e.g. Add a DPDK Phy port with MTU of 9000: - -`ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk -- set Interface dpdk0 mtu_request=9000` - -e.g. Change the MTU of an existing port to 6200: - -`ovs-vsctl set Interface dpdk0 mtu_request=6200` - -When Jumbo Frames are enabled, the size of a DPDK port's mbuf segments are -increased, such that a full Jumbo Frame of a specific size may be accommodated -within a single mbuf segment. - -Jumbo frame support has been validated against 9728B frames (largest frame size -supported by Fortville NIC), using the DPDK `i40e` driver, but larger frames -(particularly in use cases involving East-West traffic only), and other DPDK NIC -drivers may be supported. - -### 11.1 vHost Ports and Jumbo Frames - -Some additional configuration is needed to take advantage of jumbo frames with -vhost ports: - - 1. `mergeable buffers` must be enabled for vHost ports, as demonstrated in - the QEMU command line snippet below: - - ``` - '-netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \' - '-device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1,mrg_rxbuf=on' - ``` - - 2. Where virtio devices are bound to the Linux kernel driver in a guest - environment (i.e. interfaces are not bound to an in-guest DPDK driver), - the MTU of those logical network interfaces must also be increased to a - sufficiently large value. This avoids segmentation of Jumbo Frames - received in the guest. Note that 'MTU' refers to the length of the IP - packet only, and not that of the entire frame. - - To calculate the exact MTU of a standard IPv4 frame, subtract the L2 - header and CRC lengths (i.e. 18B) from the max supported frame size. - So, to set the MTU for a 9018B Jumbo Frame: - - ``` - ifconfig eth1 mtu 9000 - ``` - -## <a name="vsperf"></a> 12. Vsperf - -Vsperf project goal is to develop vSwitch test framework that can be used to -validate the suitability of different vSwitch implementations in a Telco deployment -environment. More information can be found in below link. - -https://wiki.opnfv.org/display/vsperf/VSperf+Home - - -Bug Reporting: --------------- - -Please report problems to b...@openvswitch.org. - - -[INSTALL.userspace.rst]:INSTALL.userspace.rst -[INSTALL.rst]:INSTALL.rst -[DPDK Linux GSG]: http://www.dpdk.org/doc/guides/linux_gsg/build_dpdk.html#binding-and-unbinding-network-ports-to-from-the-igb-uioor-vfio-modules -[DPDK Docs]: http://dpdk.org/doc -[libvirt]: http://libvirt.org/formatdomain.html -[Guest VM using libvirt]: INSTALL.DPDK.rst#ovstc -[Vhost walkthrough]: INSTALL.DPDK.rst#vhost -[INSTALL DPDK]: INSTALL.DPDK.rst#build -[INSTALL OVS]: INSTALL.DPDK.rst#build diff --git a/INSTALL.DPDK-ADVANCED.rst b/INSTALL.DPDK-ADVANCED.rst new file mode 100644 index 0000000..7ecbc59 --- /dev/null +++ b/INSTALL.DPDK-ADVANCED.rst @@ -0,0 +1,938 @@ +.. + Licensed under the Apache License, Version 2.0 (the "License"); you may + not use this file except in compliance with the License. You may obtain + a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the + License for the specific language governing permissions and limitations + under the License. + + Convention for heading levels in Open vSwitch documentation: + + ======= Heading 0 (reserved for the title in a document) + ------- Heading 1 + ~~~~~~~ Heading 2 + +++++++ Heading 3 + ''''''' Heading 4 + + Avoid deeper levels because they do not render well. + +================================= +Open vSwitch with DPDK (Advanced) +================================= + +The Advanced Install Guide explains how to improve OVS performance when using +DPDK datapath. This guide provides information on tuning, system configuration, +troubleshooting, static code analysis and testcases. + +Building as a Shared Library +---------------------------- + +DPDK can be built as a static or a shared library and shall be linked by +applications using DPDK datapath. When building OVS with DPDK, you can link +Open vSwitch against the shared DPDK library. + +.. note:: + Minor performance loss is seen with OVS when using shared DPDK library as + compared to static library. + +To build Open vSwitch using DPDK as a shared library, first refer to the `DPDK +installation guide`_ for download instructions for DPDK and OVS. + +Once DPDK and OVS have been downloaded, you must configure the DPDK library +accordingly. Simply set ``CONFIG_RTE_BUILD_SHARED_LIB=y`` in +``config/common_base``, then build and install DPDK. Once done, DPDK can be +built as usual. For example:: + + $ export DPDK_TARGET=x86_64-native-linuxapp-gcc + $ export DPDK_BUILD=$DPDK_DIR/$DPDK_TARGET + $ make install T=$DPDK_TARGET DESTDIR=install + +Once DPDK is built, export the DPDK shared library location and setup OVS as +detailed in the `DPDK installation guide`_:: + + $ export LD_LIBRARY_PATH=$DPDK_DIR/x86_64-native-linuxapp-gcc/lib + +System Configuration +-------------------- + +To achieve optimal OVS performance, the system can be configured and that +includes BIOS tweaks, Grub cmdline additions, better understanding of NUMA +nodes and apt selection of PCIe slots for NIC placement. + +Recommended BIOS Settings +~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. list-table:: Recommended BIOS Settings + :header-rows: 1 + + * - Setting + - Value + * - C3 Power State + - Disabled + * - C6 Power State + - Disabled + * - MLC Streamer + - Enabled + * - MLC Spacial Prefetcher + - Enabled + * - DCU Data Prefetcher + - Enabled + * - DCA + - Enabled + * - CPU Power and Performance + - Performance + * - Memeory RAS and Performance Config -> NUMA optimized + - Enabled + +PCIe Slot Selection +~~~~~~~~~~~~~~~~~~~ + +The fastpath performance can be affected by factors related to the placement of +the NIC, such as channel speeds between PCIe slot and CPU or the proximity of +PCIe slot to the CPU cores running the DPDK application. Listed below are the +steps to identify right PCIe slot. + +#. Retrieve host details using ``dmidecode``. For example:: + + $ dmidecode -t baseboard | grep "Product Name" + +#. Download the technical specification for product listed, e.g: S2600WT2 + +#. Check the Product Architecture Overview on the Riser slot placement, CPU + sharing info and also PCIe channel speeds + + For example: On S2600WT, CPU1 and CPU2 share Riser Slot 1 with Channel speed + between CPU1 and Riser Slot1 at 32GB/s, CPU2 and Riser Slot1 at 16GB/s. + Running DPDK app on CPU1 cores and NIC inserted in to Riser card Slots will + optimize OVS performance in this case. + +#. Check the Riser Card #1 - Root Port mapping information, on the available + slots and individual bus speeds. In S2600WT slot 1, slot 2 has high bus + speeds and are potential slots for NIC placement. + +Advanced Hugepage Setup +~~~~~~~~~~~~~~~~~~~~~~~ + +Allocate and mount 1 GB hugepages. + +- For persistent allocation of huge pages, add the following options to the + kernel bootline:: + + default_hugepagesz=1GB hugepagesz=1G hugepages=N + + For platforms supporting multiple huge page sizes, add multiple options:: + + default_hugepagesz=<size> hugepagesz=<size> hugepages=N + + where: + + ``N`` + number of huge pages requested + ``size`` + huge page size with an optional suffix ``[kKmMgG]`` + +- For run-time allocation of huge pages:: + + $ echo N > /sys/devices/system/node/nodeX/hugepages/hugepages-1048576kB/nr_hugepages + + where: + + ``N`` + number of huge pages requested + ``X`` + NUMA Node + + .. note:: + For run-time allocation of 1G huge pages, Contiguous Memory Allocator + (``CONFIG_CMA``) has to be supported by kernel, check your Linux distro. + +Now mount the huge pages, if not already done so:: + + $ mount -t hugetlbfs -o pagesize=1G none /dev/hugepages + +Enable HyperThreading +~~~~~~~~~~~~~~~~~~~~~ + +With HyperThreading, or SMT, enabled, a physical core appears as two logical +cores. SMT can be utilized to spawn worker threads on logical cores of the same +physical core there by saving additional cores. + +With DPDK, when pinning pmd threads to logical cores, care must be taken to set +the correct bits of the ``pmd-cpu-mask`` to ensure that the pmd threads are +pinned to SMT siblings. + +Take a sample system configuration, with 2 sockets, 2 * 10 core processors, HT +enabled. This gives us a total of 40 logical cores. To identify the physical +core shared by two logical cores, run:: + + $ cat /sys/devices/system/cpu/cpuN/topology/thread_siblings_list + +where ``N`` is the logical core number. + +In this example, it would show that cores ``1`` and ``21`` share the same +physical core., thus, the ``pmd-cpu-mask`` can be used to enable these two pmd +threads running on these two logical cores (one physical core) is:: + + $ ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=100002 + +Isolate Cores +~~~~~~~~~~~~~ + +The ``isolcpus`` option can be used to isolate cores from the Linux scheduler. +The isolated cores can then be used to dedicatedly run HPC applications or +threads. This helps in better application performance due to zero context +switching and minimal cache thrashing. To run platform logic on core 0 and +isolate cores between 1 and 19 from scheduler, add ``isolcpus=1-19`` to GRUB +cmdline. + +.. note:: + It has been verified that core isolation has minimal advantage due to mature + Linux scheduler in some circumstances. + +NUMA/Cluster-on-Die +~~~~~~~~~~~~~~~~~~~ + +Ideally inter-NUMA datapaths should be avoided where possible as packets will +go across QPI and there may be a slight performance penalty when compared with +intra NUMA datapaths. On Intel Xeon Processor E5 v3, Cluster On Die is +introduced on models that have 10 cores or more. This makes it possible to +logically split a socket into two NUMA regions and again it is preferred where +possible to keep critical datapaths within the one cluster. + +It is good practice to ensure that threads that are in the datapath are pinned +to cores in the same NUMA area. e.g. pmd threads and QEMU vCPUs responsible for +forwarding. If DPDK is built with ``CONFIG_RTE_LIBRTE_VHOST_NUMA=y``, vHost +User ports automatically detect the NUMA socket of the QEMU vCPUs and will be +serviced by a PMD from the same node provided a core on this node is enabled in +the ``pmd-cpu-mask``. ``libnuma`` packages are required for this feature. + +Compiler Optimizations +~~~~~~~~~~~~~~~~~~~~~~ + +The default compiler optimization level is ``-O2``. Changing this to more +aggressive compiler optimization such as ``-O3 -march=native`` with +gcc (verified on 5.3.1) can produce performance gains though not siginificant. +``-march=native`` will produce optimized code on local machine and should be +used when software compilation is done on Testbed. + +Performance Tuning +------------------ + +Affinity +~~~~~~~~ + +For superior performance, DPDK pmd threads and Qemu vCPU threads needs to be +affinitized accordingly. + +- PMD thread Affinity + + A poll mode driver (pmd) thread handles the I/O of all DPDK interfaces + assigned to it. A pmd thread shall poll the ports for incoming packets, + switch the packets and send to tx port. pmd thread is CPU bound, and needs + to be affinitized to isolated cores for optimum performance. + + By setting a bit in the mask, a pmd thread is created and pinned to the + corresponding CPU core. e.g. to run a pmd thread on core 2:: + + $ ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=4 + + .. note:: + pmd thread on a NUMA node is only created if there is at least one DPDK + interface from that NUMA node added to OVS. + +- QEMU vCPU thread Affinity + + A VM performing simple packet forwarding or running complex packet pipelines + has to ensure that the vCPU threads performing the work has as much CPU + occupancy as possible. + + For example, on a multicore VM, multiple QEMU vCPU threads shall be spawned. + When the DPDK ``testpmd`` application that does packet forwarding is invoked, + the ``taskset`` command should be used to affinitize the vCPU threads to the + dedicated isolated cores on the host system. + +Multiple Poll-Mode Driver Threads +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +With pmd multi-threading support, OVS creates one pmd thread for each NUMA node +by default. However, in cases where there are multiple ports/rxq's producing +traffic, performance can be improved by creating multiple pmd threads running +on separate cores. These pmd threads can share the workload by each being +responsible for different ports/rxq's. Assignment of ports/rxq's to pmd threads +is done automatically. + +A set bit in the mask means a pmd thread is created and pinned to the +corresponding CPU core. For example, to run pmd threads on core 1 and 2:: + + $ ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=6 + +When using dpdk and dpdkvhostuser ports in a bi-directional VM loopback as +shown below, spreading the workload over 2 or 4 pmd threads shows significant +improvements as there will be more total CPU occupancy available:: + + NIC port0 <-> OVS <-> VM <-> OVS <-> NIC port 1 + +DPDK Physical Port Rx Queues +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +:: + + $ ovs-vsctl set Interface <DPDK interface> options:n_rxq=<integer> + +The command above sets the number of rx queues for DPDK physical interface. +The rx queues are assigned to pmd threads on the same NUMA node in a +round-robin fashion. + +DPDK Physical Port Queue Sizes +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +:: + + $ ovs-vsctl set Interface dpdk0 options:n_rxq_desc=<integer> + $ ovs-vsctl set Interface dpdk0 options:n_txq_desc=<integer> + +The command above sets the number of rx/tx descriptors that the NIC associated +with dpdk0 will be initialised with. + +Different ``n_rxq_desc`` and ``n_txq_desc`` configurations yield different +benefits in terms of throughput and latency for different scenarios. +Generally, smaller queue sizes can have a positive impact for latency at the +expense of throughput. The opposite is often true for larger queue sizes. +Note: increasing the number of rx descriptors eg. to 4096 may have a negative +impact on performance due to the fact that non-vectorised DPDK rx functions may +be used. This is dependant on the driver in use, but is true for the commonly +used i40e and ixgbe DPDK drivers. + +Exact Match Cache +~~~~~~~~~~~~~~~~~ + +Each pmd thread contains one Exact Match Cache (EMC). After initial flow setup +in the datapath, the EMC contains a single table and provides the lowest level +(fastest) switching for DPDK ports. If there is a miss in the EMC then the next +level where switching will occur is the datapath classifier. Missing in the +EMC and looking up in the datapath classifier incurs a significant performance +penalty. If lookup misses occur in the EMC because it is too small to handle +the number of flows, its size can be increased. The EMC size can be modified by +editing the define ``EM_FLOW_HASH_SHIFT`` in ``lib/dpif-netdev.c``. + +As mentioned above, an EMC is per pmd thread. An alternative way of increasing +the aggregate amount of possible flow entries in EMC and avoiding datapath +classifier lookups is to have multiple pmd threads running. + +Rx Mergeable Buffers +~~~~~~~~~~~~~~~~~~~~ + +Rx mergeable buffers is a virtio feature that allows chaining of multiple +virtio descriptors to handle large packet sizes. Large packets are handled by +reserving and chaining multiple free descriptors together. Mergeable buffer +support is negotiated between the virtio driver and virtio device and is +supported by the DPDK vhost library. This behavior is supported and enabled by +default, however in the case where the user knows that rx mergeable buffers are +not needed i.e. jumbo frames are not needed, it can be forced off by adding +``mrg_rxbuf=off`` to the QEMU command line options. By not reserving multiple +chains of descriptors it will make more individual virtio descriptors available +for rx to the guest using dpdkvhost ports and this can improve performance. + +OVS Testcases +------------- + +PHY-VM-PHY (vHost Loopback) +~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The `DPDK installation guide`_ details steps for PHY-VM-PHY loopback testcase +and packet forwarding using DPDK testpmd application in the Guest VM. For users +wishing to do packet forwarding using kernel stack below, you need to run the +below commands on the guest:: + + $ ifconfig eth1 1.1.1.2/24 + $ ifconfig eth2 1.1.2.2/24 + $ systemctl stop firewalld.service + $ systemctl stop iptables.service + $ sysctl -w net.ipv4.ip_forward=1 + $ sysctl -w net.ipv4.conf.all.rp_filter=0 + $ sysctl -w net.ipv4.conf.eth1.rp_filter=0 + $ sysctl -w net.ipv4.conf.eth2.rp_filter=0 + $ route add -net 1.1.2.0/24 eth2 + $ route add -net 1.1.1.0/24 eth1 + $ arp -s 1.1.2.99 DE:AD:BE:EF:CA:FE + $ arp -s 1.1.1.99 DE:AD:BE:EF:CA:EE + +PHY-VM-PHY (IVSHMEM) +~~~~~~~~~~~~~~~~~~~~ + +IVSHMEM can also be validated using the PHY-VM-PHY configuration. To begin, +follow the steps described in the `DPDK installation guide`_ to create and +initialize the database, start ovs-vswitchd and add ``dpdk``-type devices to +bridge ``br0``. Once complete, follow the below steps: + +1. Add DPDK ring port to the bridge:: + + $ ovs-vsctl add-port br0 dpdkr0 -- set Interface dpdkr0 type=dpdkr + +2. Build modified QEMU + + QEMU must be patched to enable IVSHMEM support:: + + $ cd /usr/src/ + $ wget http://wiki.qemu.org/download/qemu-2.2.1.tar.bz2 + $ tar -jxvf qemu-2.2.1.tar.bz2 + $ cd /usr/src/qemu-2.2.1 + $ wget https://raw.githubusercontent.com/netgroup-polito/un-orchestrator/master/orchestrator/compute_controller/plugins/kvm-libvirt/patches/ivshmem-qemu-2.2.1.patch + $ patch -p1 < ivshmem-qemu-2.2.1.patch + $ ./configure --target-list=x86_64-softmmu --enable-debug --extra-cflags='-g' + $ make -j 4 + +3. Generate QEMU commandline:: + + $ mkdir -p /usr/src/cmdline_generator + $ cd /usr/src/cmdline_generator + $ wget https://raw.githubusercontent.com/netgroup-polito/un-orchestrator/master/orchestrator/compute_controller/plugins/kvm-libvirt/cmdline_generator/cmdline_generator.c + $ wget https://raw.githubusercontent.com/netgroup-polito/un-orchestrator/master/orchestrator/compute_controller/plugins/kvm-libvirt/cmdline_generator/Makefile + $ export RTE_SDK=/usr/src/dpdk-16.07 + $ export RTE_TARGET=x86_64-ivshmem-linuxapp-gcc + $ make + $ ./build/cmdline_generator -m -p dpdkr0 XXX + $ cmdline=`cat OVSMEMPOOL` + +4. Start guest VM:: + + $ export VM_NAME=ivshmem-vm + $ export QCOW2_IMAGE=/root/CentOS7_x86_64.qcow2 + $ export QEMU_BIN=/usr/src/qemu-2.2.1/x86_64-softmmu/qemu-system-x86_64 + $ taskset 0x20 $QEMU_BIN -cpu host -smp 2,cores=2 -hda $QCOW2_IMAGE \ + -m 4096 --enable-kvm -name $VM_NAME -nographic -vnc :2 \ + -pidfile /tmp/vm1.pid $cmdline + +5. Build and run the sample ``dpdkr`` app in VM:: + + $ echo 1024 > /proc/sys/vm/nr_hugepages + $ mount -t hugetlbfs nodev /dev/hugepages (if not already mounted) + + # Build the DPDK ring application in the VM + $ export RTE_SDK=/root/dpdk-16.07 + $ export RTE_TARGET=x86_64-ivshmem-linuxapp-gcc + $ make + + # Run dpdkring application + $ ./build/dpdkr -c 1 -n 4 -- -n 0 + # where "-n 0" refers to ring '0' i.e dpdkr0 + +PHY-VM-PHY (vHost Multiqueue) +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +vHost Multique functionality can also be validated using the PHY-VM-PHY +configuration. To begin, follow the steps described in the `DPDK installation +guide`_ to create and initialize the database, start ovs-vswitchd and add +``dpdk``-type devices to bridge ``br0``. Once complete, follow the below steps: + +1. Configure PMD and RXQs. + + For example, set the number of dpdk port rx queues to at least 2 The number + of rx queues at vhost-user interface gets automatically configured after + virtio device connection and doesn't need manual configuration:: + + $ ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=c + $ ovs-vsctl set Interface dpdk0 options:n_rxq=2 + $ ovs-vsctl set Interface dpdk1 options:n_rxq=2 + +2. Instantiate Guest VM using QEMU cmdline + + We must configure with appropriate software versions to ensure this feature + is supported. + + .. list-table:: Recommended BIOS Settings + :header-rows: 1 + + * - Setting + - Value + * - QEMU version + - 2.5.0 + * - QEMU thread affinity + - 2 cores (taskset 0x30) + * - Memory + - 4 GB + * - Cores + - 2 + * - Distro + - Fedora 22 + * - Multiqueue + - Enabled + + To do this, instantiate the guest as follows:: + + $ export VM_NAME=vhost-vm + $ export GUEST_MEM=4096M + $ export QCOW2_IMAGE=/root/Fedora22_x86_64.qcow2 + $ export VHOST_SOCK_DIR=/usr/local/var/run/openvswitch + $ taskset 0x30 qemu-system-x86_64 -cpu host -smp 2,cores=2 -m 4096M \ + -drive file=$QCOW2_IMAGE --enable-kvm -name $VM_NAME \ + -nographic -numa node,memdev=mem -mem-prealloc \ + -object memory-backend-file,id=mem,size=$GUEST_MEM,mem-path=/dev/hugepages,share=on \ + -chardev socket,id=char1,path=$VHOST_SOCK_DIR/dpdkvhostuser0 \ + -netdev type=vhost-user,id=mynet1,chardev=char1,vhostforce,queues=2 \ + -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1,mq=on,vectors=6 \ + -chardev socket,id=char2,path=$VHOST_SOCK_DIR/dpdkvhostuser1 \ + -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce,queues=2 \ + -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2,mq=on,vectors=6 + + .. note:: + Queue value above should match the queues configured in OVS, The vector + value should be set to "number of queues x 2 + 2" + +3. Configure the guest interface + + Assuming there are 2 interfaces in the guest named eth0, eth1 check the + channel configuration and set the number of combined channels to 2 for + virtio devices:: + + $ ethtool -l eth0 + $ ethtool -L eth0 combined 2 + $ ethtool -L eth1 combined 2 + + More information can be found in vHost walkthrough section. + +4. Configure kernel packet forwarding + + Configure IP and enable interfaces:: + + $ ifconfig eth0 5.5.5.1/24 up + $ ifconfig eth1 90.90.90.1/24 up + + Configure IP forwarding and add route entries:: + + $ sysctl -w net.ipv4.ip_forward=1 + $ sysctl -w net.ipv4.conf.all.rp_filter=0 + $ sysctl -w net.ipv4.conf.eth0.rp_filter=0 + $ sysctl -w net.ipv4.conf.eth1.rp_filter=0 + $ ip route add 2.1.1.0/24 dev eth1 + $ route add default gw 2.1.1.2 eth1 + $ route add default gw 90.90.90.90 eth1 + $ arp -s 90.90.90.90 DE:AD:BE:EF:CA:FE + $ arp -s 2.1.1.2 DE:AD:BE:EF:CA:FA + + Check traffic on multiple queues:: + + $ cat /proc/interrupts | grep virtio + +vHost Walkthrough +----------------- + +Two types of vHost User ports are available in OVS: + +- vhost-user (``dpdkvhostuser``) + +- vhost-user-client (``dpdkvhostuserclient``) + +vHost User uses a client-server model. The server creates/manages/destroys the +vHost User sockets, and the client connects to the server. Depending on which +port type you use, ``dpdkvhostuser`` or ``dpdkvhostuserclient``, a different +configuration of the client-server model is used. + +For vhost-user ports, Open vSwitch acts as the server and QEMU the client. For +vhost-user-client ports, Open vSwitch acts as the client and QEMU the server. + +vhost-user +~~~~~~~~~~ + +1. Install the prerequisites: + + - QEMU version >= 2.2 + +2. Add vhost-user ports to the switch. + + Unlike DPDK ring ports, DPDK vhost-user ports can have arbitrary names, + except that forward and backward slashes are prohibited in the names. + + For vhost-user, the name of the port type is ``dpdkvhostuser``:: + + $ ovs-vsctl add-port br0 vhost-user-1 -- set Interface vhost-user-1 \ + type=dpdkvhostuser + + This action creates a socket located at + ``/usr/local/var/run/openvswitch/vhost-user-1``, which you must provide to + your VM on the QEMU command line. More instructions on this can be found in + the next section "Adding vhost-user ports to VM" + + .. note:: + If you wish for the vhost-user sockets to be created in a sub-directory of + ``/usr/local/var/run/openvswitch``, you may specify this directory in the + ovsdb like so:: + + $ ovs-vsctl --no-wait \ + set Open_vSwitch . other_config:vhost-sock-dir=subdir` + +3. Add vhost-user ports to VM + + 1. Configure sockets + + Pass the following parameters to QEMU to attach a vhost-user device:: + + -chardev socket,id=char1,path=/usr/local/var/run/openvswitch/vhost-user-1 + -netdev type=vhost-user,id=mynet1,chardev=char1,vhostforce + -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1 + + where ``vhost-user-1`` is the name of the vhost-user port added to the + switch. + + Repeat the above parameters for multiple devices, changing the chardev + ``path`` and ``id`` as necessary. Note that a separate and different + chardev ``path`` needs to be specified for each vhost-user device. For + example you have a second vhost-user port named ``vhost-user-2``, you + append your QEMU command line with an additional set of parameters:: + + -chardev socket,id=char2,path=/usr/local/var/run/openvswitch/vhost-user-2 + -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce + -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2 + + 2. Configure hugepages + + QEMU must allocate the VM's memory on hugetlbfs. vhost-user ports access + a virtio-net device's virtual rings and packet buffers mapping the VM's + physical memory on hugetlbfs. To enable vhost-user ports to map the VM's + memory into their process address space, pass the following parameters + to QEMU:: + + -object memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on + -numa node,memdev=mem -mem-prealloc + + 3. Enable multiqueue support (optional) + + QEMU needs to be configured to use multiqueue:: + + -chardev socket,id=char2,path=/usr/local/var/run/openvswitch/vhost-user-2 + -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce,queues=$q + -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2,mq=on,vectors=$v + + where: + + ``$q`` + The number of queues + ``$v`` + The number of vectors, which is ``$q`` * 2 + 2 + + The vhost-user interface will be automatically reconfigured with + required number of rx and tx queues after connection of virtio device. + Manual configuration of ``n_rxq`` is not supported because OVS will work + properly only if ``n_rxq`` will match number of queues configured in + QEMU. + + A least 2 PMDs should be configured for the vswitch when using + multiqueue. Using a single PMD will cause traffic to be enqueued to the + same vhost queue rather than being distributed among different vhost + queues for a vhost-user interface. + + If traffic destined for a VM configured with multiqueue arrives to the + vswitch via a physical DPDK port, then the number of rxqs should also be + set to at least 2 for that physical DPDK port. This is required to + increase the probability that a different PMD will handle the multiqueue + transmission to the guest using a different vhost queue. + + If one wishes to use multiple queues for an interface in the guest, the + driver in the guest operating system must be configured to do so. It is + recommended that the number of queues configured be equal to ``$q``. + + For example, this can be done for the Linux kernel virtio-net driver + with:: + + $ ethtool -L <DEV> combined <$q> + + where: + + ``-L`` + Changes the numbers of channels of the specified network device + ``combined`` + Changes the number of multi-purpose channels. + +Configure the VM using libvirt +++++++++++++++++++++++++++++++ + +You can also build and configure the VM using libvirt rather than QEMU by +itself. + +1. Change the user/group, access control policty and restart libvirtd. + + - In ``/etc/libvirt/qemu.conf`` add/edit the following lines:: + + user = "root" + group = "root" + + - Disable SELinux or set to permissive mode:: + + $ setenforce 0 + + - Restart the libvirtd process, For example, on Fedora:: + + $ systemctl restart libvirtd.service + +2. Instantiate the VM + + - Copy the XML configuration described in the `DPDK installation guide`_. + + - Start the VM:: + + $ virsh create demovm.xml + + - Connect to the guest console:: + + $ virsh console demovm + +3. Configure the VM + + The demovm xml configuration is aimed at achieving out of box performance on + VM. + + - The vcpus are pinned to the cores of the CPU socket 0 using ``vcpupin``. + + - Configure NUMA cell and memory shared using ``memAccess='shared'``. + + - Disable ``mrg_rxbuf='off'`` + +Refer to the `libvirt documentation <http://libvirt.org/formatdomain.html>`__ +for more information. + +vhost-user-client +~~~~~~~~~~~~~~~~~ + +1. Install the prerequisites: + + - QEMU version >= 2.7 + +2. Add vhost-user-client ports to the switch. + + Unlike vhost-user ports, the name given to port does not govern the name of + the socket device. ``vhost-server-path`` reflects the full path of the + socket that has been or will be created by QEMU for the given vHost User + client port. + + For vhost-user-client, the name of the port type is + ``dpdkvhostuserclient``:: + + $ VHOST_USER_SOCKET_PATH=/path/to/socker + $ ovs-vsctl add-port br0 vhost-client-1 \ + -- set Interface vhost-client-1 type=dpdkvhostuserclient \ + options:vhost-server-path=$VHOST_USER_SOCKET_PATH + +3. Add vhost-user-client ports to VM + + 1. Configure sockets + + Pass the following parameters to QEMU to attach a vhost-user device:: + + -chardev socket,id=char1,path=$VHOST_USER_SOCKET_PATH,server + -netdev type=vhost-user,id=mynet1,chardev=char1,vhostforce + -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1 + + where ``vhost-user-1`` is the name of the vhost-user port added to the + switch. + + If the corresponding dpdkvhostuserclient port has not yet been configured + in OVS with ``vhost-server-path=/path/to/socket``, QEMU will print a log + similar to the following:: + + QEMU waiting for connection on: disconnected:unix:/path/to/socket,server + + QEMU will wait until the port is created sucessfully in OVS to boot the VM. + + One benefit of using this mode is the ability for vHost ports to + 'reconnect' in event of the switch crashing or being brought down. Once + it is brought back up, the vHost ports will reconnect automatically and + normal service will resume. + +DPDK Backend Inside VM +~~~~~~~~~~~~~~~~~~~~~~ + +Additional configuration is required if you want to run ovs-vswitchd with DPDK +backend inside a QEMU virtual machine. Ovs-vswitchd creates separate DPDK TX +queues for each CPU core available. This operation fails inside QEMU virtual +machine because, by default, VirtIO NIC provided to the guest is configured to +support only single TX queue and single RX queue. To change this behavior, you +need to turn on ``mq`` (multiqueue) property of all ``virtio-net-pci`` devices +emulated by QEMU and used by DPDK. You may do it manually (by changing QEMU +command line) or, if you use Libvirt, by adding the following string to +``<interface>`` sections of all network devices used by DPDK:: + + <driver name='vhost' queues='N'/> + +Where: + +``N`` + determines how many queues can be used by the guest. + +This requires QEMU >= 2.2. + +QoS +--- + +Assuming you have a vhost-user port transmitting traffic consisting of packets +of size 64 bytes, the following command would limit the egress transmission +rate of the port to ~1,000,000 packets per second:: + + $ ovs-vsctl set port vhost-user0 qos=@newqos -- \ + --id=@newqos create qos type=egress-policer other-config:cir=46000000 \ + other-config:cbs=2048` + +To examine the QoS configuration of the port, run:: + + $ ovs-appctl -t ovs-vswitchd qos/show vhost-user0 + +To clear the QoS configuration from the port and ovsdb, run:: + + $ ovs-vsctl destroy QoS vhost-user0 -- clear Port vhost-user0 qos + +Refer to vswitch.xml for more details on egress-policer. + +Rate Limiting +-------------- + +Here is an example on Ingress Policing usage. Assuming you have a vhost-user +port receiving traffic consisting of packets of size 64 bytes, the following +command would limit the reception rate of the port to ~1,000,000 packets per +second:: + + $ ovs-vsctl set interface vhost-user0 ingress_policing_rate=368000 \ + ingress_policing_burst=1000` + +To examine the ingress policer configuration of the port:: + + $ ovs-vsctl list interface vhost-user0 + +To clear the ingress policer configuration from the port:: + + $ ovs-vsctl set interface vhost-user0 ingress_policing_rate=0 + +Refer to vswitch.xml for more details on ingress-policer. + +Flow Control +------------ + +Flow control can be enabled only on DPDK physical ports. To enable flow +control support at tx side while adding a port, run:: + + $ ovs-vsctl add-port br0 dpdk0 -- \ + set Interface dpdk0 type=dpdk options:tx-flow-ctrl=true + +Similarly, to enable rx flow control, run:: + + $ ovs-vsctl add-port br0 dpdk0 -- \ + set Interface dpdk0 type=dpdk options:rx-flow-ctrl=true + +To enable flow control auto-negotiation, run:: + + $ ovs-vsctl add-port br0 dpdk0 -- \ + set Interface dpdk0 type=dpdk options:flow-ctrl-autoneg=true + +To turn ON the tx flow control at run time(After the port is being added to +OVS):: + + $ ovs-vsctl set Interface dpdk0 options:tx-flow-ctrl=true + +The flow control parameters can be turned off by setting ``false`` to the +respective parameter. To disable the flow control at tx side, run:: + + $ ovs-vsctl set Interface dpdk0 options:tx-flow-ctrl=false + +pdump +----- + +Pdump allows you to listen on DPDK ports and view the traffic that is passing +on them. To use this utility, one must have libpcap installed on the system. +Furthermore, DPDK must be built with ``CONFIG_RTE_LIBRTE_PDUMP=y`` and +``CONFIG_RTE_LIBRTE_PMD_PCAP=y``. + +.. warning:: + A performance decrease is expected when using a monitoring application like + the DPDK pdump app. + +To use pdump, simply launch OVS as usual. Then, navigate to the ``app/pdump`` +directory in DPDK, ``make`` the application and run like so:: + + $ sudo ./build/app/dpdk-pdump -- \ + --pdump port=0,queue=0,rx-dev=/tmp/pkts.pcap \ + --server-socket-path=/usr/local/var/run/openvswitch + +The above command captures traffic received on queue 0 of port 0 and stores it +in ``/tmp/pkts.pcap``. Other combinations of port numbers, queues numbers and +pcap locations are of course also available to use. For example, to capture all +packets that traverse port 0 in a single pcap file:: + + $ sudo ./build/app/dpdk-pdump -- \ + --pdump 'port=0,queue=*,rx-dev=/tmp/pkts.pcap,tx-dev=/tmp/pkts.pcap' \ + --server-socket-path=/usr/local/var/run/openvswitch + +``server-socket-path`` must be set to the value of ovs_rundir() which typically +resolves to ``/usr/local/var/run/openvswitch``. + +Many tools are available to view the contents of the pcap file. Once example is +tcpdump. Issue the following command to view the contents of ``pkts.pcap``:: + + $ tcpdump -r pkts.pcap + +More information on the pdump app and its usage can be found in the `DPDK docs +<http://dpdk.org/doc/guides/sample_app_ug/pdump.html>`__. + +Jumbo Frames +------------ + +By default, DPDK ports are configured with standard Ethernet MTU (1500B). To +enable Jumbo Frames support for a DPDK port, change the Interface's +``mtu_request`` attribute to a sufficiently large value. For example, to add a +DPDK Phy port with MTU of 9000:: + + $ ovs-vsctl add-port br0 dpdk0 \ + -- set Interface dpdk0 type=dpdk \ + -- set Interface dpdk0 mtu_request=9000` + +Similarly, to change the MTU of an existing port to 6200:: + + $ ovs-vsctl set Interface dpdk0 mtu_request=6200 + +Some additional configuration is needed to take advantage of jumbo frames with +vHost ports: + +1. *mergeable buffers* must be enabled for vHost ports, as demonstrated in the + QEMU command line snippet below:: + + -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ + -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1,mrg_rxbuf=on + +2. Where virtio devices are bound to the Linux kernel driver in a guest + environment (i.e. interfaces are not bound to an in-guest DPDK driver), the + MTU of those logical network interfaces must also be increased to a + sufficiently large value. This avoids segmentation of Jumbo Frames received + in the guest. Note that 'MTU' refers to the length of the IP packet only, + and not that of the entire frame. + + To calculate the exact MTU of a standard IPv4 frame, subtract the L2 header + and CRC lengths (i.e. 18B) from the max supported frame size. So, to set + the MTU for a 9018B Jumbo Frame:: + + $ ifconfig eth1 mtu 9000 + +When Jumbo Frames are enabled, the size of a DPDK port's mbuf segments are +increased, such that a full Jumbo Frame of a specific size may be accommodated +within a single mbuf segment. + +Jumbo frame support has been validated against 9728B frames, which is the +largest frame size supported by Fortville NIC using the DPDK i40e driver, but +larger frames and other DPDK NIC drivers may be supported. These cases are +common for use cases involving East-West traffic only. + +vsperf +------ + +The vsperf project aims to develop a vSwitch test framework that can be used to +validate the suitability of different vSwitch implementations in a telco +deployment environment. More information can be found on the `OPNFV wiki +<https://wiki.opnfv.org/display/vsperf/VSperf+Home>`__. + +Bug Reporting +------------- + +Report problems to b...@openvswitch.org. + +.. _DPDK installation guide: INSTALL.DPDK.rst diff --git a/INSTALL.DPDK.rst b/INSTALL.DPDK.rst index b917828..874f070 100644 --- a/INSTALL.DPDK.rst +++ b/INSTALL.DPDK.rst @@ -55,7 +55,7 @@ In addition to the requirements described in the `installation guide Detailed system requirements can be found at `DPDK requirements`_, while more detailed install information can be found in the `advanced installation guide -<INSTALL.DPDK-ADVANCED.md>`__. +<INSTALL.DPDK-ADVANCED.rst>`__. .. _DPDK supported NIC: http://dpdk.org/doc/nics .. _DPDK requirements: http://dpdk.org/doc/guides/linux_gsg/sys_reqs.html @@ -229,7 +229,7 @@ them to cores 1,2, run::: $ ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=6 For details on using ivshmem with DPDK, refer to `the advanced installation -guide <INSTALL.DPDK-ADVANCED.md>`__. +guide <INSTALL.DPDK-ADVANCED.rst>`__. Refer to ovs-vswitchd.conf.db(5) for additional information on configuration options. @@ -338,7 +338,7 @@ DPDK 'testpmd' application can be run in the Guest VM for high speed packet forwarding between vhostuser ports. DPDK and testpmd application has to be compiled on the guest VM. Below are the steps for setting up the testpmd application in the VM. More information on the vhostuser ports can be found in -the `advanced install guide <INSTALL.DPDK-ADVANCED.md>`__. +the `advanced install guide <INSTALL.DPDK-ADVANCED.rst>`__. .. note:: Support for DPDK in the guest requires QEMU >= 2.2.0. @@ -574,12 +574,12 @@ When you finish testing, bind the vNICs back to kernel::: .. note:: More information on the dpdkvhostuser ports can be found in the `advanced - installation guide <INSTALL.DPDK-ADVANCED.md>`__. + installation guide <INSTALL.DPDK-ADVANCED.rst>`__. PHY-VM-PHY (IVSHMEM loopback) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -Refer to the `advanced installation guide <INSTALL.DPDK-ADVANCED.md>`__. +Refer to the `advanced installation guide <INSTALL.DPDK-ADVANCED.rst>`__. Limitations ------------ diff --git a/Makefile.am b/Makefile.am index 2588389..0a77823 100644 --- a/Makefile.am +++ b/Makefile.am @@ -74,7 +74,7 @@ docs = \ INSTALL.rst \ INSTALL.Debian.rst \ INSTALL.Docker.rst \ - INSTALL.DPDK-ADVANCED.md \ + INSTALL.DPDK-ADVANCED.rst \ INSTALL.DPDK.rst \ INSTALL.Fedora.rst \ INSTALL.KVM.rst \ -- 2.7.4 _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev