Re: [ovs-dev] [PATCH 0/4] dpif-netdev: Hash-based Tx packet steering
Hi Ilya, On 12/8/21 00:23, Ilya Maximets wrote: On 11/24/21 22:23, Maxime Coquelin wrote: This series introduces a new HXPS Tx mode alognside existing XPS and static modes. The goal is to provide a mode where all the transmit queues are used, whatever the number of PMD threads. This may be used with Vhost-user ports, where the guest application driving the Virtio device expects packets to be distributed on all the queues. As a preliminary step, in order to be able to validate the feature at OVS level, the first patch introduces per-queue basic statistics for Vhost-user ports. This patch is complementary to David's patch [0] adding per-queue statistics to DPDK ports using xstats. The series also introduces two DPDK tests for Vhost-user multiqueue, with and without HXPS enabled. Maxime Coquelin (4): netdev-dpdk: Introduce per rxq/txq Vhost-user statistics dpif-netdev: Introduce Tx queue mode dpif-netdev: Add HXPS Tx queue mode system-dpdk: Add tests for HXPS Documentation/automake.mk | 1 + Documentation/topics/dpdk/hxps.rst | 51 ++ Documentation/topics/dpdk/index.rst | 1 + lib/dpif-netdev.c | 95 ++ lib/netdev-dpdk.c | 143 ++-- tests/system-dpdk.at| 135 ++ 6 files changed, 399 insertions(+), 27 deletions(-) create mode 100644 Documentation/topics/dpdk/hxps.rst Hi, Maxime. Thanks for working on this. I agree that this feature might be very useful for some deployments. I didn't read the code any carefully, just glanced at it. But I have a couple of high level comments: 1. I don't think that the test for the actual XPS mode implementation should be part of a system-dpdk testsuite, as it's not actually related to DPDK and doesn't require any system HW/ports/non-OVS applications running in order to test it. So, I think, that we should be able to do practically the same testing, but with dummy interfaces, with a test placed in the dpif-netdev.at or pmd.at (probably, latter). To achieve that you'll need per-queue stats in netdev-dummy, but implementation of these will be practically the same or even a bit simpler as you did for vhost-user ports. Per-queue stats for vhost-user ports might be good to have in general, so that patch along with some simple test in system-dpdk.at for them could be split from this patch set and sent separately. Or dropped, if you think they are not valuable (?). OK, I will work on adding per-queue stats to netdev-dummy. I agree it is better to decouple the testing of this feature from DPDK, and it will make the test being executed more often. 2. The test itself doesn't need a packet generator script, AFAICT. You may just send some number of packets via dummy port changing source or destination udp/tcp port affecting the packet hash this way. For example, see the SEND_TCP_BOND_PKTS macro in the tests/ofproto-dpif.at and how bonding rebalancing tests are using it. Thanks for the pointer on SEND_TCP_BOND_PKTS, I agree this is better this way. Also, using fuzzing as I did may have the drawback of seldomly generate packets with hashes that would make them all ending into a single queue. 3. Might be better instead of introduction of a specialized config knob (other_config:hxps=true), to have a multi-choice knob like other_config:xps-mode with 2 options 'default' and 'hash', where 'default' is a current way of tx queue distribution and it will be a default value. 'hash' will be a new mode that uses packet hash to choose the tx queue (what's implemented in this patch set). Ok, makes sense. What do you think? Those are valid points, thanks for your suggestions. Maxime Best regards, Ilya Maximets. ___ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
Re: [ovs-dev] [PATCH 0/4] dpif-netdev: Hash-based Tx packet steering
On 11/24/21 22:23, Maxime Coquelin wrote: > This series introduces a new HXPS Tx mode alognside existing > XPS and static modes. The goal is to provide a mode where all > the transmit queues are used, whatever the number of PMD > threads. This may be used with Vhost-user ports, where the > guest application driving the Virtio device expects packets > to be distributed on all the queues. > > As a preliminary step, in order to be able to validate the > feature at OVS level, the first patch introduces per-queue > basic statistics for Vhost-user ports. This patch is > complementary to David's patch [0] adding per-queue > statistics to DPDK ports using xstats. > > The series also introduces two DPDK tests for Vhost-user > multiqueue, with and without HXPS enabled. > > Maxime Coquelin (4): > netdev-dpdk: Introduce per rxq/txq Vhost-user statistics > dpif-netdev: Introduce Tx queue mode > dpif-netdev: Add HXPS Tx queue mode > system-dpdk: Add tests for HXPS > > Documentation/automake.mk | 1 + > Documentation/topics/dpdk/hxps.rst | 51 ++ > Documentation/topics/dpdk/index.rst | 1 + > lib/dpif-netdev.c | 95 ++ > lib/netdev-dpdk.c | 143 ++-- > tests/system-dpdk.at| 135 ++ > 6 files changed, 399 insertions(+), 27 deletions(-) > create mode 100644 Documentation/topics/dpdk/hxps.rst > Hi, Maxime. Thanks for working on this. I agree that this feature might be very useful for some deployments. I didn't read the code any carefully, just glanced at it. But I have a couple of high level comments: 1. I don't think that the test for the actual XPS mode implementation should be part of a system-dpdk testsuite, as it's not actually related to DPDK and doesn't require any system HW/ports/non-OVS applications running in order to test it. So, I think, that we should be able to do practically the same testing, but with dummy interfaces, with a test placed in the dpif-netdev.at or pmd.at (probably, latter). To achieve that you'll need per-queue stats in netdev-dummy, but implementation of these will be practically the same or even a bit simpler as you did for vhost-user ports. Per-queue stats for vhost-user ports might be good to have in general, so that patch along with some simple test in system-dpdk.at for them could be split from this patch set and sent separately. Or dropped, if you think they are not valuable (?). 2. The test itself doesn't need a packet generator script, AFAICT. You may just send some number of packets via dummy port changing source or destination udp/tcp port affecting the packet hash this way. For example, see the SEND_TCP_BOND_PKTS macro in the tests/ofproto-dpif.at and how bonding rebalancing tests are using it. 3. Might be better instead of introduction of a specialized config knob (other_config:hxps=true), to have a multi-choice knob like other_config:xps-mode with 2 options 'default' and 'hash', where 'default' is a current way of tx queue distribution and it will be a default value. 'hash' will be a new mode that uses packet hash to choose the tx queue (what's implemented in this patch set). What do you think? Best regards, Ilya Maximets. ___ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
Re: [ovs-dev] [PATCH 0/4] dpif-netdev: Hash-based Tx packet steering
Hi, On 11/24/21 22:23, Maxime Coquelin wrote: This series introduces a new HXPS Tx mode alognside existing XPS and static modes. The goal is to provide a mode where all the transmit queues are used, whatever the number of PMD threads. This may be used with Vhost-user ports, where the guest application driving the Virtio device expects packets to be distributed on all the queues. As a preliminary step, in order to be able to validate the feature at OVS level, the first patch introduces per-queue basic statistics for Vhost-user ports. This patch is complementary to David's patch [0] adding per-queue statistics to DPDK ports using xstats. [0]: http://patchwork.ozlabs.org/project/openvswitch/patch/20211015150406.12949-1-david.march...@redhat.com/ The series also introduces two DPDK tests for Vhost-user multiqueue, with and without HXPS enabled. I also forgot to mention that this series depends on David's system-dpdk tests refactoring series: http://patchwork.ozlabs.org/project/openvswitch/list/?series=273438 Maxime Coquelin (4): netdev-dpdk: Introduce per rxq/txq Vhost-user statistics dpif-netdev: Introduce Tx queue mode dpif-netdev: Add HXPS Tx queue mode system-dpdk: Add tests for HXPS Documentation/automake.mk | 1 + Documentation/topics/dpdk/hxps.rst | 51 ++ Documentation/topics/dpdk/index.rst | 1 + lib/dpif-netdev.c | 95 ++ lib/netdev-dpdk.c | 143 ++-- tests/system-dpdk.at| 135 ++ 6 files changed, 399 insertions(+), 27 deletions(-) create mode 100644 Documentation/topics/dpdk/hxps.rst ___ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
[ovs-dev] [PATCH 0/4] dpif-netdev: Hash-based Tx packet steering
This series introduces a new HXPS Tx mode alognside existing XPS and static modes. The goal is to provide a mode where all the transmit queues are used, whatever the number of PMD threads. This may be used with Vhost-user ports, where the guest application driving the Virtio device expects packets to be distributed on all the queues. As a preliminary step, in order to be able to validate the feature at OVS level, the first patch introduces per-queue basic statistics for Vhost-user ports. This patch is complementary to David's patch [0] adding per-queue statistics to DPDK ports using xstats. The series also introduces two DPDK tests for Vhost-user multiqueue, with and without HXPS enabled. Maxime Coquelin (4): netdev-dpdk: Introduce per rxq/txq Vhost-user statistics dpif-netdev: Introduce Tx queue mode dpif-netdev: Add HXPS Tx queue mode system-dpdk: Add tests for HXPS Documentation/automake.mk | 1 + Documentation/topics/dpdk/hxps.rst | 51 ++ Documentation/topics/dpdk/index.rst | 1 + lib/dpif-netdev.c | 95 ++ lib/netdev-dpdk.c | 143 ++-- tests/system-dpdk.at| 135 ++ 6 files changed, 399 insertions(+), 27 deletions(-) create mode 100644 Documentation/topics/dpdk/hxps.rst -- 2.31.1 ___ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
