Fix ingress bandwidth limit in the openvswitch agent
For ingress bandwidth limiting openvswitch agent is using QoS and queues
from the Open vSwitch. There is always queue 0 used for that purpose.
Initially, when this feature was implemented, we assumed that queue 0 is
kind of the "default" queue to which all traffic will be send if there
are no other queues. But that's not true thus ingress bandwidth limiting
wasn't working properly with this agent.
This patch fixes that issue but adding in the table=0 of the br-int
additional OF rule to send all traffic to the queue 0.
In this queue for some ports there can be QoS configured
and then it will be applied for the port. If port don't have any QoS
configured, nothing will happen and all will work like before this
patch.
Biggest problem with that solution was the case when also ports with
minimum bandwidth are on the same node becuase such ports are using
different queues (queue number is the same as ofport number of the tap
interface).
In case when traffic is going from the port with minimum bandwidth QoS
to the port which has ingress bw limit configured, traffic is going only
through br-int and will use queue 0 to apply ingress bw limit properly.
In case when traffic from port with minimum bandwidth set needs to go
out from the host, it will always use physical bridge (minimum bandwidth
is only supported for the provider networks) and proper queue will be
set for such traffic in the physical bridge.
To be able to set proper queue in the physical bridge, this patch adds
additional OF rule to the br-int to set queue_num value in the pkt_mark
field [1] as this seems to be only field which can "survive" passing
bridges.
Reviewed: https:/ /review. opendev. org/c/openstack /neutron/ +/835944 /opendev. org/openstack/ neutron/ commit/ 6af566a89a1bc03 889ff666c73fa7a 7dcf131061
Committed: https:/
Submitter: "Zuul (22348)"
Branch: stable/wallaby
commit 6af566a89a1bc03 889ff666c73fa7a 7dcf131061
Author: Slawek Kaplonski <email address hidden>
Date: Tue Mar 8 16:44:59 2022 +0100
Fix ingress bandwidth limit in the openvswitch agent
For ingress bandwidth limiting openvswitch agent is using QoS and queues
from the Open vSwitch. There is always queue 0 used for that purpose.
Initially, when this feature was implemented, we assumed that queue 0 is
kind of the "default" queue to which all traffic will be send if there
are no other queues. But that's not true thus ingress bandwidth limiting
wasn't working properly with this agent.
This patch fixes that issue but adding in the table=0 of the br-int
additional OF rule to send all traffic to the queue 0.
In this queue for some ports there can be QoS configured
and then it will be applied for the port. If port don't have any QoS
configured, nothing will happen and all will work like before this
patch.
Biggest problem with that solution was the case when also ports with
minimum bandwidth are on the same node becuase such ports are using
different queues (queue number is the same as ofport number of the tap
interface).
In case when traffic is going from the port with minimum bandwidth QoS
to the port which has ingress bw limit configured, traffic is going only
through br-int and will use queue 0 to apply ingress bw limit properly.
In case when traffic from port with minimum bandwidth set needs to go
out from the host, it will always use physical bridge (minimum bandwidth
is only supported for the provider networks) and proper queue will be
set for such traffic in the physical bridge.
To be able to set proper queue in the physical bridge, this patch adds
additional OF rule to the br-int to set queue_num value in the pkt_mark
field [1] as this seems to be only field which can "survive" passing
bridges.
[1] https:/ /man7.org/ linux/man- pages/man7/ ovs-fields. 7.html
Closes-Bug: #1959567 6ad817268699b16 5759ac05410 cfb94bc8b9450cd 915ea49c03) 242ab54eb85b8e3 6f33f79403)
Change-Id: I1e31565475f38c
(cherry picked from commit f7ab90baad83823
(cherry picked from commit 5573230d30a7beb