| Message ID | 20180416143026.24561-9-stephen@that.guru |
|---|---|
| State | Changes Requested |
| Delegated to: | Ian Stokes |
| Headers | show |
| Series | Split up the DPDK how-to | expand |
> We include refrences from the physical and vhost-user interface guides. Minor type above, 'reference'. > > Signed-off-by: Stephen Finucane <stephen@that.guru> > --- > v2: > - Don't split the document into multiple docs > --- > Documentation/howto/dpdk.rst | 52 ++-------------------- > Documentation/topics/dpdk/index.rst | 1 + > Documentation/topics/dpdk/jumbo-frames.rst | 71 > ++++++++++++++++++++++++++++++ > Documentation/topics/dpdk/phy.rst | 6 +++ > Documentation/topics/dpdk/vhost-user.rst | 6 +++ > 5 files changed, 87 insertions(+), 49 deletions(-) create mode 100644 > Documentation/topics/dpdk/jumbo-frames.rst > > diff --git a/Documentation/howto/dpdk.rst b/Documentation/howto/dpdk.rst > index 1a0fb6df1..e65e7dfaa 100644 > --- a/Documentation/howto/dpdk.rst > +++ b/Documentation/howto/dpdk.rst > @@ -48,9 +48,9 @@ number of dpdk devices found in the log file:: > $ ovs-vsctl add-port br0 dpdk-p1 -- set Interface dpdk-p1 type=dpdk \ > options:dpdk-devargs=0000:01:00.1 > > -Some NICs (i.e. Mellanox ConnectX-3) have only one PCI address associated > -with multiple ports. Using a PCI device like above won't work. Instead, > below -usage is suggested:: > +Some NICs (i.e. Mellanox ConnectX-3) have only one PCI address > +associated with multiple ports. Using a PCI device like above won't > +work. Instead, below usage is suggested:: > > $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > options:dpdk-devargs="class=eth,mac=00:11:22:33:44:55:01" > @@ -85,52 +85,6 @@ To stop ovs-vswitchd & delete bridge, run:: > $ ovs-appctl -t ovsdb-server exit > $ ovs-vsctl del-br br0 > > -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 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > - options:dpdk-devargs=0000:01:00.0 mtu_request=9000 > - > -Similarly, to change the MTU of an existing port to 6200:: > - > - $ ovs-vsctl set Interface dpdk-p0 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:: > - > - $ ip link set 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. > - > .. _dpdk-ovs-in-guest: > > OVS with DPDK Inside VMs > diff --git a/Documentation/topics/dpdk/index.rst > b/Documentation/topics/dpdk/index.rst > index d083d929e..181f61abb 100644 > --- a/Documentation/topics/dpdk/index.rst > +++ b/Documentation/topics/dpdk/index.rst > @@ -39,3 +39,4 @@ The DPDK Datapath > /topics/dpdk/pmd > /topics/dpdk/qos > /topics/dpdk/pdump > + /topics/dpdk/jumbo-frames > diff --git a/Documentation/topics/dpdk/jumbo-frames.rst > b/Documentation/topics/dpdk/jumbo-frames.rst > new file mode 100644 > index 000000000..692b291ac > --- /dev/null > +++ b/Documentation/topics/dpdk/jumbo-frames.rst Compilation error, jumbo-frames.rst not listed in Documentation/automake.mk. Also was introduced in OVS 2.6, version change tag could flag this. Ian > @@ -0,0 +1,71 @@ > +.. > + Copyright 2018, Red Hat, Inc. > + > + 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. > + > +============ > +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 :doc:`DPDK physical port <phy>` with an MTU of > 9000, run:: > + > + $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ > + options:dpdk-devargs=0000:01:00.0 mtu_request=9000 > + > +Similarly, to change the MTU of an existing port to 6200, run:: > + > + $ ovs-vsctl set Interface dpdk-p0 mtu_request=6200 > + > +Some additional configuration is needed to take advantage of jumbo > +frames with :doc:`vHost User ports <vhost-user>`: > + > +- *Mergeable buffers* must be enabled for vHost User 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 > + > +- 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:: > + > + $ ip link set 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. > diff --git a/Documentation/topics/dpdk/phy.rst > b/Documentation/topics/dpdk/phy.rst > index c0931b2c4..477b291e4 100644 > --- a/Documentation/topics/dpdk/phy.rst > +++ b/Documentation/topics/dpdk/phy.rst > @@ -218,3 +218,9 @@ If the log is not seen then the port can be detached > like so:: > For more information please refer to the `DPDK Port Hotplug Framework`__. > > __ > http://dpdk.org/doc/guides/prog_guide/port_hotplug_framework.html#hotplug > + > +Jumbo Frames > +------------ > + > +DPDK physical ports can be configured to use Jumbo Frames. For more > +information, refer to :doc:`jumbo-frames`. > diff --git a/Documentation/topics/dpdk/vhost-user.rst > b/Documentation/topics/dpdk/vhost-user.rst > index 168d5c5ce..67eb77d43 100644 > --- a/Documentation/topics/dpdk/vhost-user.rst > +++ b/Documentation/topics/dpdk/vhost-user.rst > @@ -444,6 +444,12 @@ Sample XML > > .. _QEMU documentation: http://git.qemu- > project.org/?p=qemu.git;a=blob;f=docs/specs/vhost- > user.txt;h=7890d7169;hb=HEAD > > +Jumbo Frames > +------------ > + > +DPDK vHost User ports can be configured to use Jumbo Frames. For more > +information, refer to :doc:`jumbo-frames`. > + > vhost-user Dequeue Zero Copy (experimental) > ------------------------------------------- > > -- > 2.14.3
diff --git a/Documentation/howto/dpdk.rst b/Documentation/howto/dpdk.rst index 1a0fb6df1..e65e7dfaa 100644 --- a/Documentation/howto/dpdk.rst +++ b/Documentation/howto/dpdk.rst @@ -48,9 +48,9 @@ number of dpdk devices found in the log file:: $ ovs-vsctl add-port br0 dpdk-p1 -- set Interface dpdk-p1 type=dpdk \ options:dpdk-devargs=0000:01:00.1 -Some NICs (i.e. Mellanox ConnectX-3) have only one PCI address associated -with multiple ports. Using a PCI device like above won't work. Instead, below -usage is suggested:: +Some NICs (i.e. Mellanox ConnectX-3) have only one PCI address associated with +multiple ports. Using a PCI device like above won't work. Instead, below usage +is suggested:: $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ options:dpdk-devargs="class=eth,mac=00:11:22:33:44:55:01" @@ -85,52 +85,6 @@ To stop ovs-vswitchd & delete bridge, run:: $ ovs-appctl -t ovsdb-server exit $ ovs-vsctl del-br br0 -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 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ - options:dpdk-devargs=0000:01:00.0 mtu_request=9000 - -Similarly, to change the MTU of an existing port to 6200:: - - $ ovs-vsctl set Interface dpdk-p0 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:: - - $ ip link set 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. - .. _dpdk-ovs-in-guest: OVS with DPDK Inside VMs diff --git a/Documentation/topics/dpdk/index.rst b/Documentation/topics/dpdk/index.rst index d083d929e..181f61abb 100644 --- a/Documentation/topics/dpdk/index.rst +++ b/Documentation/topics/dpdk/index.rst @@ -39,3 +39,4 @@ The DPDK Datapath /topics/dpdk/pmd /topics/dpdk/qos /topics/dpdk/pdump + /topics/dpdk/jumbo-frames diff --git a/Documentation/topics/dpdk/jumbo-frames.rst b/Documentation/topics/dpdk/jumbo-frames.rst new file mode 100644 index 000000000..692b291ac --- /dev/null +++ b/Documentation/topics/dpdk/jumbo-frames.rst @@ -0,0 +1,71 @@ +.. + Copyright 2018, Red Hat, Inc. + + 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. + +============ +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 +:doc:`DPDK physical port <phy>` with an MTU of 9000, run:: + + $ ovs-vsctl add-port br0 dpdk-p0 -- set Interface dpdk-p0 type=dpdk \ + options:dpdk-devargs=0000:01:00.0 mtu_request=9000 + +Similarly, to change the MTU of an existing port to 6200, run:: + + $ ovs-vsctl set Interface dpdk-p0 mtu_request=6200 + +Some additional configuration is needed to take advantage of jumbo frames with +:doc:`vHost User ports <vhost-user>`: + +- *Mergeable buffers* must be enabled for vHost User 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 + +- 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:: + + $ ip link set 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. diff --git a/Documentation/topics/dpdk/phy.rst b/Documentation/topics/dpdk/phy.rst index c0931b2c4..477b291e4 100644 --- a/Documentation/topics/dpdk/phy.rst +++ b/Documentation/topics/dpdk/phy.rst @@ -218,3 +218,9 @@ If the log is not seen then the port can be detached like so:: For more information please refer to the `DPDK Port Hotplug Framework`__. __ http://dpdk.org/doc/guides/prog_guide/port_hotplug_framework.html#hotplug + +Jumbo Frames +------------ + +DPDK physical ports can be configured to use Jumbo Frames. For more +information, refer to :doc:`jumbo-frames`. diff --git a/Documentation/topics/dpdk/vhost-user.rst b/Documentation/topics/dpdk/vhost-user.rst index 168d5c5ce..67eb77d43 100644 --- a/Documentation/topics/dpdk/vhost-user.rst +++ b/Documentation/topics/dpdk/vhost-user.rst @@ -444,6 +444,12 @@ Sample XML .. _QEMU documentation: http://git.qemu-project.org/?p=qemu.git;a=blob;f=docs/specs/vhost-user.txt;h=7890d7169;hb=HEAD +Jumbo Frames +------------ + +DPDK vHost User ports can be configured to use Jumbo Frames. For more +information, refer to :doc:`jumbo-frames`. + vhost-user Dequeue Zero Copy (experimental) -------------------------------------------
We include refrences from the physical and vhost-user interface guides. Signed-off-by: Stephen Finucane <stephen@that.guru> --- v2: - Don't split the document into multiple docs --- Documentation/howto/dpdk.rst | 52 ++-------------------- Documentation/topics/dpdk/index.rst | 1 + Documentation/topics/dpdk/jumbo-frames.rst | 71 ++++++++++++++++++++++++++++++ Documentation/topics/dpdk/phy.rst | 6 +++ Documentation/topics/dpdk/vhost-user.rst | 6 +++ 5 files changed, 87 insertions(+), 49 deletions(-) create mode 100644 Documentation/topics/dpdk/jumbo-frames.rst