> On 16 May 2023, at 23:54, Numan Siddique <[email protected]> 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 <[email protected] > <mailto:[email protected]>> 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 <[email protected]> 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 <[email protected]> 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 >> >> 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); >> 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; > > 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); >> >> 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? > > > >> >> >>>> >>>> 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? >>>> 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. > > 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? >>>> 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/[email protected]/ >> 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 >> [email protected] <mailto:[email protected]> >> https://mail.openvswitch.org/mailman/listinfo/ovs-dev Regards, Vladislav Odintsov _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
