Hi Han, thanks for your inputs! Please see comments inline.
> On 5 Jun 2023, at 21:01, Han Zhou <hz...@ovn.org> wrote: > > On Mon, Jun 5, 2023 at 8:58 AM Vladislav Odintsov <odiv...@gmail.com > <mailto:odiv...@gmail.com>> wrote: >> >> Hi Dumitru, Ilya, Han, >> >> do you guys have any comments here? >> I’m gonna start working on this change in near future... >> >> Thank you. >> >> On 17 May 2023, at 18:34, Numan Siddique <num...@ovn.org >> <mailto:num...@ovn.org>> wrote: >> >> On Wed, May 17, 2023 at 4:44 AM Vladislav Odintsov <odiv...@gmail.com >> <mailto:odiv...@gmail.com>> > wrote: >> >> >> >> >> On 16 May 2023, at 23:54, Numan Siddique <num...@ovn.org >> <mailto:num...@ovn.org>> wrote: >> >> Hi Vladislav, >> >> Sorry for the late reply. >> >> PSB for few comments. >> >> >> >> Thanks for your reply! >> My answers are inline. >> >> >> >> >> On Tue, May 16, 2023 at 3:42 PM Vladislav Odintsov <odiv...@gmail.com >> <mailto:odiv...@gmail.com> > <mailto:odiv...@gmail.com>> wrote: >> >> >> Hi Numan, Dumitru, Ilya, >> >> I guess I’ve managed to deal with some of these problems and have some > conclusions. >> Please see inline. >> >> On 14 Apr 2023, at 16:26, Vladislav Odintsov <odiv...@gmail.com >> <mailto:odiv...@gmail.com>> wrote: >> >> And as a follow-up, I see sometimes next error message in ovn-controller > log, though there is a configured much higher limit in seconds for > inactivity probe value for the chassis: >> >> >> ovn-controller establishes 3 openflow connections to local ovs-vswitchd > for next purposes: >> 1. openflow rules management (openflow probe interval is configured > through ovn-openflow-probe-interval external_ids setting [1]; default — > disabled [2]); >> 2. openflow features collection (hardcoded probe interval 5s [3]); >> 3. pinctrl thread (hardcoded probe interval 5s [4]). >> >> ovs|04426|rconn|ERR|unix:/run/openvswitch/br-int.mgmt: no response to > inactivity probe after 8 seconds, disconnecting >> >> ovs|26560|rconn|ERR|unix:/run/openvswitch/br-int.mgmt: no response to > inactivity probe after 10 seconds, disconnecting >> >> >> These messages most likely related to the connection for features > collection or pinctrl thread. So ovn-openflow-probe-interval has no matter > here. >> >> >> server with first log message: >> # ovs-vsctl get open . external_ids:ovn-openflow-probe-interval >> "30" >> >> server with second log message: >> # ovs-vsctl get open . external_ids:ovn-openflow-probe-interval >> "60" >> >> >> >> On 30 Mar 2023, at 23:19, Vladislav Odintsov <odiv...@gmail.com >> <mailto:odiv...@gmail.com>> wrote: >> >> Hi all, >> >> I’m facing a false positive failover in the event of openflow connection > got dropped after inactivity probe timeout due to high load of > ovn-controller handling huge amount of ovsdb updates. >> I wonder wether its a bug or I have to tune any specifics. See > ovn-controller logs: >> >> 2023-03-30T07:57:24.469Z|58440|inc_proc_eng|INFO|node: > logical_flow_output, recompute (failed handler for input port_groups) took > 35774ms >> 2023-03-30T07:57:28.521Z|58441|lflow_cache|INFO|Detected cache inactivity > (last active 40006 ms ago): trimming cache >> 2023-03-30T07:57:28.528Z|58442|timeval|WARN|Unreasonably long 40084ms > poll interval (32947ms user, 6968ms system) >> 2023-03-30T07:57:28.528Z|58443|timeval|WARN|faults: 43468 minor, 0 major >> ….. >> 2023-03-30T07:57:48.784Z|58496|reconnect|ERR|ssl:xxxx:6642: no response > to inactivity probe after 60.2 seconds, disconnecting >> 2023-03-30T07:57:48.784Z|58497|reconnect|INFO|ssl:xxxx:6642: connection > dropped >> 2023-03-30T07:57:48.905Z|58498|main|INFO|OVNSB commit failed, force > recompute next time. >> 2023-03-30T07:57:49.786Z|58499|reconnect|INFO|ssl:yyyy:6642: connecting... >> 2023-03-30T07:57:49.924Z|58500|reconnect|INFO|ssl:yyyy:6642: connected >> 2023-03-30T07:57:29.781Z|58501|poll_loop|INFO|wakeup due to 0-ms timeout > at lib/stream-ssl.c:838 (74% CPU usage) >> 2023-03-30T07:57:29.836Z|58502|poll_loop|INFO|wakeup due to 0-ms timeout > at lib/stream-ssl.c:838 (74% CPU usage) >> …. >> 2023-03-30T07:57:05.976Z|58545|poll_loop|INFO|wakeup due to 0-ms timeout > at lib/stream-ssl.c:838 (101% CPU usage) >> 2023-03-30T07:57:07.002Z|58546|memory|INFO|peak resident set size grew > 54% in last 682257.2 seconds, from 4435696 kB to 6824820 kB >> > 2023-03-30T07:57:07.002Z|58547|memory|INFO|idl-cells-OVN_Southbound:11491359 > idl-cells-Open_vSwitch:14416 lflow-cache-entries-cache-expr:530298 > lflow-cache-entries-cache-matches:31770 lflow-cache-size-KB:769553 > local_datapath_usage-KB:630 >> ofctrl_desired_flow_usage-KB:577052 ofctrl_installed_flow_usage-KB:409538 > ofctrl_sb_flow_ref_usage-KB:273707 >> … >> > 2023-03-30T07:57:31.667Z|58552|rconn|WARN|unix:/run/openvswitch/br-int.mgmt: > connection dropped (Broken pipe) >> 2023-03-30T07:57:31.739Z|58553|binding|INFO|Releasing lport cr-xxx from > this chassis (sb_readonly=0) >> 2023-03-30T07:57:31.739Z|58554|if_status|WARN|Dropped 1 log messages in > last 1254725 seconds (most recently, 1254725 seconds ago) due to excessive > rate >> 2023-03-30T07:57:31.739Z|58555|if_status|WARN|Trying to release unknown > interface cr-xxx >> 2023-03-30T07:57:31.743Z|58556|binding|INFO|Releasing lport cr-yyy from > this chassis (sb_readonly=0) >> 2023-03-30T07:57:31.743Z|58557|binding|INFO|Releasing lport cr-zzz from > this chassis (sb_readonly=0) >> … >> >> After some time these ports are claimed back: >> >> > 2023-03-30T07:57:49.320Z|59137|rconn|INFO|unix:/run/openvswitch/br-int.mgmt: > connecting... >> > 2023-03-30T07:57:49.320Z|59138|rconn|INFO|unix:/run/openvswitch/br-int.mgmt: > connected >> 2023-03-30T07:57:49.523Z|59139|poll_loop|INFO|wakeup due to 0-ms timeout > at controller/ovn-controller.c:4296 (99% CPU usage) >> 2023-03-30T07:57:49.574Z|59140|poll_loop|INFO|wakeup due to 0-ms timeout > at controller/ovn-controller.c:4286 (99% CPU usage) >> 2023-03-30T07:58:01.451Z|59141|poll_loop|INFO|wakeup due to [POLLIN] on > fd 22 (xxxx:34736<->yyyy:6642) at lib/stream-ssl.c:836 (99% CPU usage) >> 2023-03-30T07:58:02.449Z|59142|binding|INFO|Claiming lport cr-xxx for > this chassis. >> 2023-03-30T07:58:02.449Z|59143|binding|INFO|cr-xxx: Claiming > xx:xx:xx:xx:xx x.x.x.x/xx >> 2023-03-30T07:58:02.453Z|59144|binding|INFO|Claiming lport cr-yyy for > this chassis. >> 2023-03-30T07:58:02.453Z|59145|binding|INFO|cr-yyy: Claiming > yy:yy:yy:yy:yy:yy y.y.y.y/yy >> … >> >> Previously I’ve met with similar problem but the openflow probe interval > was 30 seconds and I set it to 60 and then to 120 seconds. >> But it seems that OVS was configured on default inactivity probe timeout > for openflow - 60 seconds. So, the error above occured. In OVS logs it > looks like next: >> >> 2023-03-30T07:57:28.632Z|61003|rconn|ERR|br-int<->unix#8: no response to > inactivity probe after 60 seconds, disconnecting >> >> >> When ovn-controller looses openflow connection for flows management it > considers OVS is dead and releases its ha-chassis-group bindings. This > logic was introduced with the patch [5]. >> >> ovn-controller uses unix socket to connect to ovs-vswitchd OF socket, it > seems useless to configure inactivity probing, right? >> In this commit message [6] Han also disables OF inactivity probing by > default. >> >> Moreover, it seems harmful to configure inactivity probing from OVS to > ovn-controller and vise versa. >> In case ovn-controller for some reason is busy with some work and can’t > answer to OVS in two minutes (its default probe interval is 60s [7]), so > OVS destroys OF connection with the ERR log: >> ovs|18206|rconn|ERR|br-int<->unix#17574: no response to inactivity probe > after 60 seconds, disconnecting >> >> So, when ovn-controller resumes after a big work it sees that OF > connection is closed and triggers chassisredirect portbindings release. >> This leads to datapath downtime and unnesessary load on OVN_Southbound, > ovn-controllers, etc. >> >> To avoid such behaviour user may consider not to configure > ovn-openflow-probe-interval AND disable probing from OVS side with the next > command: >> ovs-vsctl --inactivity-probe=0 set-controller br-int > punix://var/run/openvswitch/br-int.mgmt > > Did you test this? It seems for the management controller it is hardcoded > to 60s: > https://github.com/openvswitch/ovs/blob/master/vswitchd/bridge.c#L3882 > >> >> To make this setting applied, it’s needed to reestablish OF connection. > (for instance, restart ovn-controller) >> >> My proposal: >> >> If ovn-controller uses only unix socket for OF connection, it should be > safe to disable OF probing from its code: >> 1. configure controller for br-int to disable probing (ensure br-int or > other configured bridge controller created with inactivity probe = 0); > > Do you mean the OVS side config (using ovs-vsctl)? But there is no code > change from OVN side, right? Yes, I mean OVS side configuration can be done by ovn-controller (it just needs to make an equivalent to mentioned command through ovsdb). > >> 2. delete ovn-openflow-probe-interval setting and mark in documentation > that for OVN versions >= 20.09 it’s recommended not to configure > ovn-openflow-inactivity-probe. For versions < 20.09 default interval is 5 > seconds, so it’s reasonable to set it to higher value in the config for > loaded hypervisors; >> > I am ok with this. For the documentation, it should be ok to remove the > related description and update the NEWS. I think there is no need to > mention 20.09 or any specific version, because documentation always belongs > to the version where it is updated. Okay, this makes sense. Documentation change could be backported to relevant branches. > >> >> You mean 23.09 right ? >> >> >> No. >> IIUC, the 20.03.0-2 and 20.06.0-2 versions have default interval of 5 > seconds. >> All other versions have disabled OF probing by default. >> So my idea was to mention it in docs and recommend users of those > versions (with 5 seconds default) to disable OF manually by setting > ovs-vsctl set open . external_ids:ovn-openflow-probe-interval=0. >> >> >> >> 3. set openflow probe interval for ovs features and pinctrl OF connection > to 0 (disable probing); >> > I am ok with this, too. > >> What do you guys think about this? >> Please, correct me if I understand something wrong and described changes > can’t be accepted. >> >> >> The proposal looks reasonable to me. >> >> There may be once concern. Let's say the physical link is fine (where >> vswitchd runs bfd) but vswitchd is down on chassis 'A' for some >> reason. With probing disabled, ovn-controller will never >> come to know if vswitchd is down until it tries to communicate with >> it. If this chassis 'A' is acting as a gateway, external traffic >> from other chassis VMs will be tunnelled to this and since vswitchd is >> down the traffic may not go out if no datapath flows exist to output >> the traffic to the physical interface of the provider bridge. Is this >> acceptable ? >> At least with the probing enabled, ovn-controller will release the >> chassis resident port and the next in the priority will claim it. >> >> IMO, this limitation is more acceptable than the issue you reported. >> Let's see what others have to say about this. >> >> >> >> I’m not sure I fully understand your idea about vswitchd down. >> I tried to send sigkill to ovs-vswitchd with probing disabled and > ovn-controller recognized the failure (connection closed by peer) and > released its chassisredirect port_binding (assuming another chassis by > priority claims it): >> >> > 2023-05-17T08:37:10.134Z|00004|rconn(ovn_pinctrl0)|INFO|unix:/run/openvswitch/br-int.mgmt: > connection closed by peer >> > 2023-05-17T08:37:10.134Z|00061|rconn|INFO|unix:/run/openvswitch/br-int.mgmt: > connection closed by peer >> > 2023-05-17T08:37:10.134Z|00062|rconn|INFO|unix:/run/openvswitch/br-int.mgmt: > connection closed by peer >> 2023-05-17T08:37:10.135Z|00063|binding|INFO|Releasing lport cr-xxx from > this chassis (sb_readonly=0) >> 2023-05-17T08:37:10.135Z|00064|if_status|WARN|Trying to release unknown > interface cr-xxx >> 2023-05-17T08:37:10.135Z|00065|binding|INFO|Releasing lport cr-xxx from > this chassis (sb_readonly=0) >> >> Does such test look reasonable and covers your concern? If not, could you > describe it in more details, please? >> >> >> I think I misunderstood earlier. Please ignore my comment. So when >> ovs-vswitchd is killed, ovn-controller will detect it. >> >> >> Thanks >> Numan >> >> >> >> >> >> >> >> >> >> This node is a dedicated l3gateway which has is-interconn=true setting > (interconnection case) and has quite big openflow table around 2.7M flows. >> >> So, I’ve got some questions for OVN and OVS: >> 1. I couldn’t find in ovn-controller code where the logic of handling > openflow connection drop. It is a bug when after openflow connection drop > the claimed cr-ports are being released? I guess, yes. Can you please point > me to the corrent place of code to start investigating? > > When openflow connection drops, ovn-controller would wait for it to > reconnect and then trigger a recompute. It seems expected behavior that the > cr-ports are released during this time. > >> 2. I see almost the same openflow amount on each l3gateway with > interconnection role. Even l3gateways which have no allocated > cr-port-bindings have 2M+ openflow flows. Is it normal operation or it’s a > place for possible optimisation? I mean it seems that excess flows are > installed. >> >> >> There are a lot of mac_binding records, but the question is why these > flows still persist even if no datapaths are allocated to the node. >> > > Does the l3gateway chassis that has no cr-port-bindings have any other > port-bindings at all? Did you observe same amount of flows if there is no > port-bindings after you restart ovn-controller? > I think there shouldn't be any flows if there is no port-bindings, but the > flows are expected if this l3gateway had port-bindings earlier and then > released them, because the incremental-processing doesn't take care of > removing local-datapaths not in use anymore. You’re right. There are no so much flows after restart. Thanks. > >> >> Maybe the datapath to which the mac binding records belong is in the >> ovn-controllers' "local_datapath" [1] - >> https://github.com/ovn-org/ovn/blob/main/controller/local_data.h#L35 >> >> >> Thanks, I’ll check that. >> >> >> 3. How to handle long OVS OF updates, which block inactivity probe for OF > connection and then got dropped? From ovn-controller it’s possible to > configure inactivity probe, is it possible and should I configure from > ovs-vswitchd side? > > The probe is always two-sides. As you mentioned you can disable the probe > from ovn-controller side. From OVS side, for my understanding it is > hardcoded to 60s. (Please confirm if your ovs-vsctl command override the > setting) > I guess, it’s hardcoded the default value. Here (https://github.com/openvswitch/ovs/blob/v3.1.0/vswitchd/bridge.c#L3930-L3933) its overridden with configured controller from ovsdb. Also, I see that provided command (ovs-vsctl set-controller … inactivity_probe=0) really disables probes from ovs to ovn-controller in my tests. > Thanks, > Han > >> 4. There is a warning on try to release unknown interface, which was > relased right before. Is it normal situation or also should be investigated? >> >> >> I think it can be ignored. Maybe @Dumitru Ceara can correct me or > comment here >> >> Thanks >> Numan >> >> >> >> For points 2-4 I still haven’t found the answer yet. If someone knows the > answer, please share it. >> >> >> Thanks. >> >> Regards, >> Vladislav Odintsov >> >> >> >> Regards, >> Vladislav Odintsov >> >> >> >> 1: https://github.com/ovn-org/ovn/blob/v23.03.0/controller/ofctrl.c#L421 >> 2: > https://github.com/ovn-org/ovn/blob/v23.03.0/controller/ovn-controller.c#L108 >> 3: https://github.com/ovn-org/ovn/blob/v23.03.0/lib/features.c#L85 >> 4: https://github.com/ovn-org/ovn/blob/v23.03.0/controller/pinctrl.c#L3479 >> 5: > https://patchwork.ozlabs.org/project/openvswitch/patch/20190204165031.31696-1-nusid...@redhat.com/ >> 6: > https://github.com/ovn-org/ovn/commit/b8af8549396e62d6523be18e104352e334825783 >> 7: https://github.com/openvswitch/ovs/blob/v3.1.0/vswitchd/bridge.c#L3860 >> >> Regards, >> Vladislav Odintsov >> >> >> >> >> >> >> Regards, >> Vladislav Odintsov >> >> _______________________________________________ >> dev mailing list >> d...@openvswitch.org <mailto:d...@openvswitch.org> >> https://mail.openvswitch.org/mailman/listinfo/ovs-dev >> >> >> >> Regards, >> Vladislav Odintsov >> >> _______________________________________________ >> dev mailing list >> d...@openvswitch.org >> https://mail.openvswitch.org/mailman/listinfo/ovs-dev >> >> _______________________________________________ >> dev mailing list >> d...@openvswitch.org <mailto:d...@openvswitch.org> >> https://mail.openvswitch.org/mailman/listinfo/ovs-dev >> >> >> >> Regards, >> Vladislav Odintsov >> > _______________________________________________ > dev mailing list > d...@openvswitch.org <mailto:d...@openvswitch.org> > https://mail.openvswitch.org/mailman/listinfo/ovs-dev Regards, Vladislav Odintsov _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
