199d788e4b
Removed RTE_SCHED_COLLECT_STATS flag from rte_config.h. Stats collection is always enabled. Signed-off-by: Megha Ajmera <megha.ajmera@intel.com> Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>
241 lines
10 KiB
ReStructuredText
241 lines
10 KiB
ReStructuredText
.. SPDX-License-Identifier: BSD-3-Clause
|
|
Copyright(c) 2010-2014 Intel Corporation.
|
|
|
|
QoS Scheduler Sample Application
|
|
================================
|
|
|
|
The QoS sample application demonstrates the use of the DPDK to provide QoS scheduling.
|
|
|
|
Overview
|
|
--------
|
|
|
|
The architecture of the QoS scheduler application is shown in the following figure.
|
|
|
|
.. _figure_qos_sched_app_arch:
|
|
|
|
.. figure:: img/qos_sched_app_arch.*
|
|
|
|
QoS Scheduler Application Architecture
|
|
|
|
|
|
There are two flavors of the runtime execution for this application,
|
|
with two or three threads per each packet flow configuration being used.
|
|
The RX thread reads packets from the RX port,
|
|
classifies the packets based on the double VLAN (outer and inner) and
|
|
the lower byte of the IP destination address and puts them into the ring queue.
|
|
The worker thread dequeues the packets from the ring and calls the QoS scheduler enqueue/dequeue functions.
|
|
If a separate TX core is used, these are sent to the TX ring.
|
|
Otherwise, they are sent directly to the TX port.
|
|
The TX thread, if present, reads from the TX ring and write the packets to the TX port.
|
|
|
|
Compiling the Application
|
|
-------------------------
|
|
|
|
To compile the sample application see :doc:`compiling`.
|
|
|
|
The application is located in the ``qos_sched`` sub-directory.
|
|
|
|
.. note::
|
|
|
|
This application is intended as a linux only.
|
|
|
|
.. note::
|
|
|
|
Number of grinders is currently set to 8.
|
|
This can be modified by specifying RTE_SCHED_PORT_N_GRINDERS=N
|
|
in CFLAGS, where N is number of grinders.
|
|
|
|
Running the Application
|
|
-----------------------
|
|
|
|
.. note::
|
|
|
|
In order to run the application, a total of at least 4
|
|
G of huge pages must be set up for each of the used sockets (depending on the cores in use).
|
|
|
|
The application has a number of command line options:
|
|
|
|
.. code-block:: console
|
|
|
|
./<build_dir>/examples/dpdk-qos_sched [EAL options] -- <APP PARAMS>
|
|
|
|
Mandatory application parameters include:
|
|
|
|
* --pfc "RX PORT, TX PORT, RX LCORE, WT LCORE, TX CORE": Packet flow configuration.
|
|
Multiple pfc entities can be configured in the command line,
|
|
having 4 or 5 items (if TX core defined or not).
|
|
|
|
Optional application parameters include:
|
|
|
|
* -i: It makes the application to start in the interactive mode.
|
|
In this mode, the application shows a command line that can be used for obtaining statistics while
|
|
scheduling is taking place (see interactive mode below for more information).
|
|
|
|
* --mnc n: Main core index (the default value is 1).
|
|
|
|
* --rsz "A, B, C": Ring sizes:
|
|
|
|
* A = Size (in number of buffer descriptors) of each of the NIC RX rings read
|
|
by the I/O RX lcores (the default value is 128).
|
|
|
|
* B = Size (in number of elements) of each of the software rings used
|
|
by the I/O RX lcores to send packets to worker lcores (the default value is 8192).
|
|
|
|
* C = Size (in number of buffer descriptors) of each of the NIC TX rings written
|
|
by worker lcores (the default value is 256)
|
|
|
|
* --bsz "A, B, C, D": Burst sizes
|
|
|
|
* A = I/O RX lcore read burst size from the NIC RX (the default value is 64)
|
|
|
|
* B = I/O RX lcore write burst size to the output software rings,
|
|
worker lcore read burst size from input software rings,QoS enqueue size (the default value is 64)
|
|
|
|
* C = QoS dequeue size (the default value is 32)
|
|
|
|
* D = Worker lcore write burst size to the NIC TX (the default value is 64)
|
|
|
|
* --msz M: Mempool size (in number of mbufs) for each pfc (default 2097152)
|
|
|
|
* --rth "A, B, C": The RX queue threshold parameters
|
|
|
|
* A = RX prefetch threshold (the default value is 8)
|
|
|
|
* B = RX host threshold (the default value is 8)
|
|
|
|
* C = RX write-back threshold (the default value is 4)
|
|
|
|
* --tth "A, B, C": TX queue threshold parameters
|
|
|
|
* A = TX prefetch threshold (the default value is 36)
|
|
|
|
* B = TX host threshold (the default value is 0)
|
|
|
|
* C = TX write-back threshold (the default value is 0)
|
|
|
|
* --cfg FILE: Profile configuration to load
|
|
|
|
Refer to *DPDK Getting Started Guide* for general information on running applications and
|
|
the Environment Abstraction Layer (EAL) options.
|
|
|
|
The profile configuration file defines all the port/subport/pipe/traffic class/queue parameters
|
|
needed for the QoS scheduler configuration.
|
|
|
|
The profile file has the following format:
|
|
|
|
.. literalinclude:: ../../../examples/qos_sched/profile.cfg
|
|
:start-after: Data Plane Development Kit (DPDK) Programmer's Guide
|
|
|
|
Interactive mode
|
|
~~~~~~~~~~~~~~~~
|
|
|
|
These are the commands that are currently working under the command line interface:
|
|
|
|
* Control Commands
|
|
|
|
* --quit: Quits the application.
|
|
|
|
* General Statistics
|
|
|
|
* stats app: Shows a table with in-app calculated statistics.
|
|
|
|
* stats port X subport Y: For a specific subport, it shows the number of packets that
|
|
went through the scheduler properly and the number of packets that were dropped.
|
|
The same information is shown in bytes.
|
|
The information is displayed in a table separating it in different traffic classes.
|
|
|
|
* stats port X subport Y pipe Z: For a specific pipe, it shows the number of packets that
|
|
went through the scheduler properly and the number of packets that were dropped.
|
|
The same information is shown in bytes.
|
|
This information is displayed in a table separating it in individual queues.
|
|
|
|
* Average queue size
|
|
|
|
All of these commands work the same way, averaging the number of packets throughout a specific subset of queues.
|
|
|
|
Two parameters can be configured for this prior to calling any of these commands:
|
|
|
|
* qavg n X: n is the number of times that the calculation will take place.
|
|
Bigger numbers provide higher accuracy. The default value is 10.
|
|
|
|
* qavg period X: period is the number of microseconds that will be allowed between each calculation.
|
|
The default value is 100.
|
|
|
|
The commands that can be used for measuring average queue size are:
|
|
|
|
* qavg port X subport Y: Show average queue size per subport.
|
|
|
|
* qavg port X subport Y tc Z: Show average queue size per subport for a specific traffic class.
|
|
|
|
* qavg port X subport Y pipe Z: Show average queue size per pipe.
|
|
|
|
* qavg port X subport Y pipe Z tc A: Show average queue size per pipe for a specific traffic class.
|
|
|
|
* qavg port X subport Y pipe Z tc A q B: Show average queue size of a specific queue.
|
|
|
|
Example
|
|
~~~~~~~
|
|
|
|
The following is an example command with a single packet flow configuration:
|
|
|
|
.. code-block:: console
|
|
|
|
./<build_dir>/examples/dpdk-qos_sched -l 1,5,7 -n 4 -- --pfc "3,2,5,7" --cfg ./profile.cfg
|
|
|
|
This example uses a single packet flow configuration which creates one RX thread on lcore 5 reading
|
|
from port 3 and a worker thread on lcore 7 writing to port 2.
|
|
|
|
Another example with 2 packet flow configurations using different ports but sharing the same core for QoS scheduler is given below:
|
|
|
|
.. code-block:: console
|
|
|
|
./<build_dir>/examples/dpdk-qos_sched -l 1,2,6,7 -n 4 -- --pfc "3,2,2,6,7" --pfc "1,0,2,6,7" --cfg ./profile.cfg
|
|
|
|
Note that independent cores for the packet flow configurations for each of the RX, WT and TX thread are also supported,
|
|
providing flexibility to balance the work.
|
|
|
|
The EAL coremask/corelist is constrained to contain the default main core 1 and the RX, WT and TX cores only.
|
|
|
|
Explanation
|
|
-----------
|
|
|
|
The Port/Subport/Pipe/Traffic Class/Queue are the hierarchical entities in a typical QoS application:
|
|
|
|
* A subport represents a predefined group of users.
|
|
|
|
* A pipe represents an individual user/subscriber.
|
|
|
|
* A traffic class is the representation of a different traffic type with a specific loss rate,
|
|
delay and jitter requirements; such as data voice, video or data transfers.
|
|
|
|
* A queue hosts packets from one or multiple connections of the same type belonging to the same user.
|
|
|
|
The traffic flows that need to be configured are application dependent.
|
|
This application classifies based on the QinQ double VLAN tags and the IP destination address as indicated in the following table.
|
|
|
|
.. _table_qos_scheduler_1:
|
|
|
|
.. table:: Entity Types
|
|
|
|
+----------------+-------------------------+--------------------------------------------------+----------------------------------+
|
|
| **Level Name** | **Siblings per Parent** | **QoS Functional Description** | **Selected By** |
|
|
| | | | |
|
|
+================+=========================+==================================================+==================================+
|
|
| Port | - | Ethernet port | Physical port |
|
|
| | | | |
|
|
+----------------+-------------------------+--------------------------------------------------+----------------------------------+
|
|
| Subport | Config (8) | Traffic shaped (token bucket) | Outer VLAN tag |
|
|
| | | | |
|
|
+----------------+-------------------------+--------------------------------------------------+----------------------------------+
|
|
| Pipe | Config (4k) | Traffic shaped (token bucket) | Inner VLAN tag |
|
|
| | | | |
|
|
+----------------+-------------------------+--------------------------------------------------+----------------------------------+
|
|
| Traffic Class | 13 | TCs of the same pipe services in strict priority | Destination IP address (0.0.0.X) |
|
|
| | | | |
|
|
+----------------+-------------------------+--------------------------------------------------+----------------------------------+
|
|
| Queue | High Priority TC: 1, | Queue of lowest priority traffic | Destination IP address (0.0.0.X) |
|
|
| | Lowest Priority TC: 4 | class (Best effort) serviced in WRR | |
|
|
+----------------+-------------------------+--------------------------------------------------+----------------------------------+
|
|
|
|
Please refer to the "QoS Scheduler" chapter in the *DPDK Programmer's Guide* for more information about these parameters.
|