On Tue, Jul 9, 2019 at 12:25 PM Daniel Alvarez Sanchez <[email protected]> wrote:
> Thanks Numan for running these tests outside OpenStack! > > On Tue, Jul 9, 2019 at 7:50 AM Numan Siddique <[email protected]> wrote: > > > > > > > > On Tue, Jul 9, 2019 at 11:05 AM Han Zhou <[email protected]> wrote: > >> > >> > >> > >> On Fri, Jun 21, 2019 at 12:31 AM Han Zhou <[email protected]> wrote: > >> > > >> > > >> > > >> > On Thu, Jun 20, 2019 at 11:42 PM Numan Siddique <[email protected]> > wrote: > >> > > > >> > > > >> > > > >> > > On Fri, Jun 21, 2019, 11:47 AM Han Zhou <[email protected]> wrote: > >> > >> > >> > >> > >> > >> > >> > >> On Tue, Jun 11, 2019 at 9:16 AM Daniel Alvarez Sanchez < > [email protected]> wrote: > >> > >> > > >> > >> > Thanks a lot Han for the answer! > >> > >> > > >> > >> > On Tue, Jun 11, 2019 at 5:57 PM Han Zhou <[email protected]> > wrote: > >> > >> > > > >> > >> > > > >> > >> > > > >> > >> > > > >> > >> > > On Tue, Jun 11, 2019 at 5:12 AM Dumitru Ceara < > [email protected]> wrote: > >> > >> > > > > >> > >> > > > On Tue, Jun 11, 2019 at 10:40 AM Daniel Alvarez Sanchez > >> > >> > > > <[email protected]> wrote: > >> > >> > > > > > >> > >> > > > > Hi Han, all, > >> > >> > > > > > >> > >> > > > > Lucas, Numan and I have been doing some 'scale' testing of > OpenStack > >> > >> > > > > using OVN and wanted to present some results and issues > that we've > >> > >> > > > > found with the Incremental Processing feature in > ovn-controller. Below > >> > >> > > > > is the scenario that we executed: > >> > >> > > > > > >> > >> > > > > * 7 baremetal nodes setup: 3 controllers (running > >> > >> > > > > ovn-northd/ovsdb-servers in A/P with pacemaker) + 4 > compute nodes. OVS > >> > >> > > > > 2.10. > >> > >> > > > > * The test consists on: > >> > >> > > > > - Create openstack network (OVN LS), subnet and router > >> > >> > > > > - Attach subnet to the router and set gw to the external > network > >> > >> > > > > - Create an OpenStack port and apply a Security Group > (ACLs to allow > >> > >> > > > > UDP, SSH and ICMP). > >> > >> > > > > - Bind the port to one of the 4 compute nodes (randomly) > by > >> > >> > > > > attaching it to a network namespace. > >> > >> > > > > - Wait for the port to be ACTIVE in Neutron ('up == > True' in NB) > >> > >> > > > > - Wait until the test can ping the port > >> > >> > > > > * Running browbeat/rally with 16 simultaneous process to > execute the > >> > >> > > > > test above 150 times. > >> > >> > > > > * When all the 150 'fake VMs' are created, browbeat will > delete all > >> > >> > > > > the OpenStack/OVN resources. > >> > >> > > > > > >> > >> > > > > We first tried with OVS/OVN 2.10 and pulled some results > which showed > >> > >> > > > > 100% success but ovn-controller is quite loaded (as > expected) in all > >> > >> > > > > the nodes especially during the deletion phase: > >> > >> > > > > > >> > >> > > > > - Compute node: https://imgur.com/a/tzxfrIR > >> > >> > > > > - Controller node (ovn-northd and ovsdb-servers): > https://imgur.com/a/8ffKKYF > >> > >> > > > > > >> > >> > > > > After conducting the tests above, we replaced > ovn-controller in all 7 > >> > >> > > > > nodes by the one with the current master branch (actually > from last > >> > >> > > > > week). We also replaced ovn-northd and ovsdb-servers but > the > >> > >> > > > > ovs-vswitchd has been left untouched (still on 2.10). The > expected > >> > >> > > > > results were to get less ovn-controller CPU usage and also > better > >> > >> > > > > times due to the Incremental Processing feature introduced > recently. > >> > >> > > > > However, the results don't look very good: > >> > >> > > > > > >> > >> > > > > - Compute node: https://imgur.com/a/wuq87F1 > >> > >> > > > > - Controller node (ovn-northd and ovsdb-servers): > https://imgur.com/a/99kiyDp > >> > >> > > > > > >> > >> > > > > One thing that we can tell from the ovs-vswitchd CPU > consumption is > >> > >> > > > > that it's much less in the Incremental Processing (IP) > case which > >> > >> > > > > apparently doesn't make much sense. This led us to think > that perhaps > >> > >> > > > > ovn-controller was not installing the necessary flows in > the switch > >> > >> > > > > and we confirmed this hypothesis by looking into the > dataplane > >> > >> > > > > results. Out of the 150 VMs, 10% of them were unreachable > via ping > >> > >> > > > > when using ovn-controller from master. > >> > >> > > > > > >> > >> > > > > @Han, others, do you have any ideas as of what could be > happening > >> > >> > > > > here? We'll be able to use this setup for a few more days > so let me > >> > >> > > > > know if you want us to pull some other data/traces, ... > >> > >> > > > > > >> > >> > > > > Some other interesting things: > >> > >> > > > > On each of the compute nodes, (with an almost evenly > distributed > >> > >> > > > > number of logical ports bound to them), the max amount of > logical > >> > >> > > > > flows in br-int is ~90K (by the end of the test, right > before deleting > >> > >> > > > > the resources). > >> > >> > > > > > >> > >> > > > > It looks like with the IP version, ovn-controller leaks > some memory: > >> > >> > > > > https://imgur.com/a/trQrhWd > >> > >> > > > > While with OVS 2.10, it remains pretty flat during the > test: > >> > >> > > > > https://imgur.com/a/KCkIT4O > >> > >> > > > > >> > >> > > > Hi Daniel, Han, > >> > >> > > > > >> > >> > > > I just sent a small patch for the ovn-controller memory leak: > >> > >> > > > https://patchwork.ozlabs.org/patch/1113758/ > >> > >> > > > > >> > >> > > > At least on my setup this is what valgrind was pointing at. > >> > >> > > > > >> > >> > > > Cheers, > >> > >> > > > Dumitru > >> > >> > > > > >> > >> > > > > > >> > >> > > > > Looking forward to hearing back :) > >> > >> > > > > Daniel > >> > >> > > > > > >> > >> > > > > PS. Sorry for my previous email, I sent it by mistake > without the subject > >> > >> > > > > _______________________________________________ > >> > >> > > > > discuss mailing list > >> > >> > > > > [email protected] > >> > >> > > > > https://mail.openvswitch.org/mailman/listinfo/ovs-discuss > >> > >> > > > >> > >> > > Thanks Daniel for the testing and reporting, and thanks > Dumitru for fixing the memory leak. > >> > >> > > > >> > >> > > Currently ovn-controller incremental processing only handles > below SB changes incrementally: > >> > >> > > - logical_flow > >> > >> > > - port_binding (for regular VIF binding NOT on current chassis) > >> > >> > > - mc_group > >> > >> > > - address_set > >> > >> > > - port_group > >> > >> > > - mac_binding > >> > >> > > > >> > >> > > So, in test scenario you described, since each iteration > creates network (SB datapath changes) and router ports (port_binding > changes for non VIF), the incremental processing would not help much, > because most steps in your test should trigger recompute. It would help if > you create more Fake VMs in each iteration, e.g. create 10 VMs or more on > each LS. Secondly, when VIF port-binding happens on current chassis, the > ovn-controller will still do re-compute, and because you have only 4 > compute nodes, so 1/4 of the compute node will still recompute even when > binding a regular VIF port. When you have more compute nodes you would see > incremental processing more effective. > >> > >> > > >> > >> > Got it, it makes sense (although then worst case, it should be at > >> > >> > least what we had before and not worse but it can also be because > >> > >> > we're mixing version here: 2.10 vs master). > >> > >> > > > >> > >> > > However, what really worries me is the 10% VM unreachable. I > have one confusion here on the test steps. The last step you described was: > - Wait until the test can ping the port. So if the VM is not pingable the > test won't continue? > >> > >> > > >> > >> > Sorry I should've explained it better. We wait for 2 minutes to > the > >> > >> > port to respond to pings, if it's not reachable then we continue > with > >> > >> > the next port (16 rally processes are running simultaneously so > the > >> > >> > rest of the process may be doing stuff at the same time). > >> > >> > > >> > >> > > > >> > >> > > To debug the problem, the first thing is to identify what > flows are missing for the VMs that is unreachable. Could you do ovs-appctl > ofproto/trace for the ICMP flow of any VM with ping failure? And then, > please enable debug log for ovn-controller with ovs-appctl -t > ovn-controller vlog/set file:dbg. There may be too many logs so please > enable it for as short time as any VM with ping failure is reproduced. If > the last step "wait until the test can ping the port" is there then it > should be able to detect the first occurrence if the VM is not reachable in > e.g. 30 sec. > >> > >> > > >> > >> > We'll need to hack a bit here but let's see :) > >> > >> > > > >> > >> > > In the ovn-scale-test we didn't have data plane test, but this > problem was not seen in our live environment either, with a far larger > scale. The major difference in your test v.s. our environment are: > >> > >> > > - We are runing with an older version. So there might be some > rebase/refactor problem caused this. To eliminate this, I'd suggest to try > a branch I created for 2.10 ( > https://github.com/hzhou8/ovs/tree/ip12_rebase_on_2.10), which matches > the base test you did which is also 2.10. It may also eliminate > compatibility problem, if there is any, between OVN master branch and OVS > 2.10 as you mentioned is used in the test. > >> > >> > > - We don't use Security Group (I guess the ~90k OVS flows you > mentioned were mainly introduced by the Security Group use, if all ports > were put in same group). The incremental processing is expected to be > correct for security-groups, and handling it incrementally because of > address_set and port_group incremental processing. However, since the > testing only relied on the regression tests, I am not 100% sure if the test > coverage was sufficient. So could you try disabling Security Group to rule > out the problem? > >> > >> > > >> > >> > Ok will try to repeat the tests without the SGs. > >> > >> > > > >> > >> > > Thanks, > >> > >> > > Han > >> > >> > > >> > >> > Thanks once again! > >> > >> > Daniel > >> > >> > >> > >> Hi Daniel, > >> > >> > >> > >> Any updates? Do you still see the 10% VM unreachable > >> > >> > >> > >> > >> > >> Thanks, > >> > >> Han > >> > > > >> > > > >> > > Hi Han, > >> > > > >> > > As such there is no datapath impact. After increasing the ping wait > timeout value from 120 seconds to 180 seconds its 100% now. > >> > > > >> > > But the time taken to program the flows is too huge when compared > to OVN master without IP patches. > >> > > Here is some data - http://paste.openstack.org/show/753224/ . I > am still investigating it. I will update my findings in some time. > >> > > > >> > > Please see the times for the action - vm.wait_for_ping > >> > > > >> > > >> > Thanks Numan for the investigation and update. Glad to hear there is > no correctness issue, but sorry for the slowness in your test scenario. I > expect that the operations in your test trigger recomputing and the worst > case should be similar performance as withour I-P. It is weird that it > turned out so much slower in your test. There can be some extra overhead > when it tries to do incremental processing and then fallback to full > recompute, but it shouldn't cause that big difference. It might be that for > some reason the main loop iteration is triggered more times unnecessarily. > I'd suggest to compare the coverage counter "lflow_run" between the tests, > and also check perf report to see if the hotspot is somewhere else. (Sorry > that I can't provide full-time help now since I am still on vacation but I > will try to be useful if things are blocked) > >> > >> Hi Numan/Daniel, do you have any new findings on why I-P got worse > result in your test? The extremely long latency (2 - 3 min) shown in your > report reminds me a similar problem I reported before: > https://mail.openvswitch.org/pipermail/ovs-dev/2018-April/346321.html > >> > >> The root cause of that problem was still not clear. In that report, the > extremely long latency (7 min) was observed without I-P and it didn't > happen with I-P. If it is the same problem, then I suspect it is not > related to I-P or non I-P, but some problem related to ovsdb monitor > condition change. To confirm if it is same problem, could you: > >> 1. pause the test when the scale is big enough (e.g. when the test is > almost completed), and then > >> 2. enable ovn-controller debug log, and then > >> 3. run one more iteration of the test, and see if the time was spent on > waiting for SB DB update notification. > >> > >> Please ignore my speculation above if you already found the root cause > and it would be great if you could share it :) > > > > > > Thanks for sharing this Han. > > > > I do not have any new findings. Yesterday I ran ovn-scale-test comparing > OVN with IP vs without IP (using the master branch). > > The test creates a new logical switch, adds it to a router, few ACLs and > creates 2 logical ports and pings between them. > > I am using physical deployment which creates actual namespaces instead > of sandboxes. > > > > The results doesn't show any huge difference between the two. > 2300 vs 2900 seconds total time or 44 vs 56 seconds for the 95%ile? > It is not negligible IMHO. It's a >25% penalty with the IP. Maybe I > missed something from the results? > > Initially I ran with ovn-nbctl running commands as one batch (ie combining commands with "--"). The results were very similar. Like this one ******* With non IP - ovn-nbctl NO daemon mode +--------------------------------------------------------------------------------------------------------------+ | Response Times (sec) | +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ | action | min | median | 90%ile | 95%ile | max | avg | success | count | +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ | ovn_network.create_routers | 0.288 | 0.429 | 5.454 | 5.538 | 20.531 | 1.523 | 100.0% | 1000 | | ovn.create_lswitch | 0.046 | 0.139 | 0.202 | 5.084 | 10.259 | 0.441 | 100.0% | 1000 | | ovn_network.connect_network_to_router | 0.164 | 0.411 | 5.307 | 5.491 | 15.636 | 1.128 | 100.0% | 1000 | | ovn.create_lport | 0.11 | 0.272 | 0.478 | 5.284 | 15.496 | 0.835 | 100.0% | 1000 | | ovn_network.bind_port | 1.302 | 2.367 | 2.834 | 3.24 | 12.409 | 2.527 | 100.0% | 1000 | | ovn_network.wait_port_up | 0.0 | 0.001 | 0.001 | 0.001 | 0.002 | 0.001 | 100.0% | 1000 | | ovn_network.ping_ports | 0.04 | 10.24 | 10.397 | 10.449 | 10.82 | 6.767 | 100.0% | 1000 | | total | 2.219 | 13.903 | 23.068 | 24.538 | 49.437 | 13.222 | 100.0% | 1000 | +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ With IP - ovn-nbctl NO daemon mode concurrency - 10 +--------------------------------------------------------------------------------------------------------------+ | Response Times (sec) | +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ | action | min | median | 90%ile | 95%ile | max | avg | success | count | +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ | ovn_network.create_routers | 0.274 | 0.402 | 0.493 | 0.51 | 0.584 | 0.408 | 100.0% | 1000 | | ovn.create_lswitch | 0.064 | 0.137 | 0.213 | 0.244 | 0.33 | 0.146 | 100.0% | 1000 | | ovn_network.connect_network_to_router | 0.203 | 0.395 | 0.677 | 0.766 | 0.912 | 0.427 | 100.0% | 1000 | | ovn.create_lport | 0.13 | 0.261 | 0.437 | 0.497 | 0.604 | 0.283 | 100.0% | 1000 | | ovn_network.bind_port | 1.307 | 2.374 | 2.816 | 2.904 | 3.401 | 2.325 | 100.0% | 1000 | | ovn_network.wait_port_up | 0.0 | 0.001 | 0.001 | 0.001 | 0.002 | 0.001 | 100.0% | 1000 | | ovn_network.ping_ports | 0.028 | 10.237 | 10.422 | 10.474 | 11.281 | 6.453 | 100.0% | 1000 | | total | 2.251 | 13.631 | 14.822 | 15.008 | 15.901 | 10.044 | 100.0% | 1000 | +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ ***************** The results I shared in the previous email were with ACLs added and ovn-nbctl - batch mode disabled. I agree with you. Let me do few more runs to be sure that the results are consistent. Thanks Numan > I will test with OVN 2.9 vs 2.11 master along with what you have > suggested above and see if there are any problems related to ovsdb monitor > condition change. > > > > Thanks > > Numan > > > > Below are the results > > > > > > With IP master - nbctl daemon node - No batch mode > > concurrency - 10 > > > > > +--------------------------------------------------------------------------------------------------------------+ > > | Response Times (sec) > | > > > +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ > > | action | min | median | 90%ile | > 95%ile | max | avg | success | count | > > > +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ > > | ovn_network.create_routers | 0.269 | 0.661 | 10.426 | > 15.422 | 37.259 | 3.721 | 100.0% | 1000 | > > | ovn.create_lswitch | 0.313 | 0.45 | 12.107 | > 15.373 | 30.405 | 4.185 | 100.0% | 1000 | > > | ovn_network.connect_network_to_router | 0.163 | 0.255 | 10.121 | > 10.64 | 20.475 | 2.655 | 100.0% | 1000 | > > | ovn.create_lport | 0.351 | 0.514 | 12.255 | > 15.511 | 34.74 | 4.621 | 100.0% | 1000 | > > | ovn_network.bind_port | 1.362 | 2.447 | 7.34 | > 7.651 | 17.651 | 3.146 | 100.0% | 1000 | > > | ovn_network.wait_port_up | 0.086 | 2.734 | 5.272 | > 7.827 | 22.717 | 2.957 | 100.0% | 1000 | > > | ovn_network.ping_ports | 0.038 | 10.196 | 20.285 | > 20.39 | 40.74 | 7.52 | 100.0% | 1000 | > > | total | 2.862 | 27.267 | 49.956 | > 56.39 | 90.884 | 28.808 | 100.0% | 1000 | > > > +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ > > Load duration: 2950.4133141 > > Full duration: 2951.58845997 seconds > > > > *********** > > With non IP - nbctl daemin node -ACLs - No batch mode > > > > concurrency - 10 > > > > > +--------------------------------------------------------------------------------------------------------------+ > > | Response Times (sec) > | > > > +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ > > | action | min | median | 90%ile | > 95%ile | max | avg | success | count | > > > +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ > > | ovn_network.create_routers | 0.267 | 0.421 | 10.395 | > 10.735 | 25.501 | 3.09 | 100.0% | 1000 | > > | ovn.create_lswitch | 0.314 | 0.408 | 10.331 | > 10.483 | 25.357 | 3.049 | 100.0% | 1000 | > > | ovn_network.connect_network_to_router | 0.153 | 0.249 | 6.552 | > 10.268 | 20.545 | 2.236 | 100.0% | 1000 | > > | ovn.create_lport | 0.344 | 0.49 | 10.566 | > 15.428 | 25.542 | 3.906 | 100.0% | 1000 | > > | ovn_network.bind_port | 1.372 | 2.409 | 7.437 | > 7.665 | 17.518 | 3.192 | 100.0% | 1000 | > > | ovn_network.wait_port_up | 0.086 | 1.323 | 5.157 | > 7.769 | 20.166 | 2.291 | 100.0% | 1000 | > > | ovn_network.ping_ports | 0.034 | 2.077 | 10.347 | > 10.427 | 20.307 | 5.123 | 100.0% | 1000 | > > | total | 3.109 | 21.26 | 39.245 | > 44.495 | 70.197 | 22.889 | 100.0% | 1000 | > > > +---------------------------------------+-------+--------+--------+--------+--------+--------+---------+-------+ > > Load duration: 2328.11378407 > > Full duration: 2334.43504095 seconds > > > > > >> > >> > >> Thanks, > >> Han >
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