| Message ID | 20210701054522.162291-1-hzhou@ovn.org |
|---|---|
| Headers | show |
| Series | Avoid parsing non-local lflows with the help of tags in SB. | expand |
Hi Han, I finally got around to having a look at this, and honestly I'm really happy at how simple the series is. For now, I'm not giving individual notes on patches, but I'll comment on the series as a whole. It seems that this is targeted at deployments where logical switches have their ports distributed across multiple HVs. Something like the OpenShift/ovn-kubernetes model of having one logical switch per node is not going to see much benefit from this series. However, this also isn't likely to add any extra overhead to that sort of deployment either. I think this is a good basis for an optimization. The biggest improvement I can think of is to be able to apply the port hint to more flows than just the ones that explicitly reference the inport or outport. But I think that could be an incremental improvement over this initial patch series. The only other criticism is the lack of DDLog, but as you noted in the description, that's a known shortcoming. On 7/1/21 1:45 AM, Han Zhou wrote: > With the help of a new column in Logical_Flow table that stores ingress/egress > lport information, ovn-controller can avoid parsing a big portion of the > logical flows in SB DB, which can largely improve ovn-controller's performance > whenever a full recompute is required. > > With a scale test topology of 1000 chassises, 20 LSPs per chassis, 20k > lports in total spread acrossing 200 logical switches, connected by a > logical router, the test result before & after this change: > > Before: > - lflow-cache disabled: > - ovn-controller recompute: 2.7 sec > - lflow-cache enabled: > - ovn-controller recompute: 2.1 sec > - lflow cache memory: 622103 KB > > After: > - lflow-cache disabled: > - ovn-controller recompute: 0.83 sec > - lflow-cache enabled: > - ovn-controller recompute: 0.71 sec > - lflow cache memory: 123641 KB > > (note: DP group enabled for both) > > So for this test scenario, when lflow cache is disabled, latency reduced > ~70%; when lflow cache is enabled, latency reduced ~65% and lflow cache > memory reduced ~80%. > > TODO: DDlog change for ovn-northd. > > Note that this series applies on top of a pending patch: > https://patchwork.ozlabs.org/project/ovn/patch/20210629192257.1699504-1-hzhou@ovn.org/ > > Han Zhou (4): > ovn-northd.at: Minor improvement for the dp group test case. > ovn-sb: Add tags column to logical_flow table of the SB DB. > ovn-northd: Populate in_out_port in logical_flow table's tags. > ovn-controller: Skip non-local lflows in ovn-controller before > parsing. > > controller/lflow.c | 21 +++ > controller/lflow.h | 1 + > controller/ovn-controller.c | 1 + > northd/ovn-northd.c | 272 ++++++++++++++++++++---------------- > ovn-sb.ovsschema | 7 +- > ovn-sb.xml | 23 +++ > tests/ovn-northd.at | 2 +- > 7 files changed, 207 insertions(+), 120 deletions(-) >
With the help of a new column in Logical_Flow table that stores ingress/egress lport information, ovn-controller can avoid parsing a big portion of the logical flows in SB DB, which can largely improve ovn-controller's performance whenever a full recompute is required. With a scale test topology of 1000 chassises, 20 LSPs per chassis, 20k lports in total spread acrossing 200 logical switches, connected by a logical router, the test result before & after this change: Before: - lflow-cache disabled: - ovn-controller recompute: 2.7 sec - lflow-cache enabled: - ovn-controller recompute: 2.1 sec - lflow cache memory: 622103 KB After: - lflow-cache disabled: - ovn-controller recompute: 0.83 sec - lflow-cache enabled: - ovn-controller recompute: 0.71 sec - lflow cache memory: 123641 KB (note: DP group enabled for both) So for this test scenario, when lflow cache is disabled, latency reduced ~70%; when lflow cache is enabled, latency reduced ~65% and lflow cache memory reduced ~80%. TODO: DDlog change for ovn-northd. Note that this series applies on top of a pending patch: https://patchwork.ozlabs.org/project/ovn/patch/20210629192257.1699504-1-hzhou@ovn.org/ Han Zhou (4): ovn-northd.at: Minor improvement for the dp group test case. ovn-sb: Add tags column to logical_flow table of the SB DB. ovn-northd: Populate in_out_port in logical_flow table's tags. ovn-controller: Skip non-local lflows in ovn-controller before parsing. controller/lflow.c | 21 +++ controller/lflow.h | 1 + controller/ovn-controller.c | 1 + northd/ovn-northd.c | 272 ++++++++++++++++++++---------------- ovn-sb.ovsschema | 7 +- ovn-sb.xml | 23 +++ tests/ovn-northd.at | 2 +- 7 files changed, 207 insertions(+), 120 deletions(-)