[ovs-dev] [OVN] ovn-controller takes 100% cpu while no changes in sb-db

[Tony Liu]

Hi,

Here are some logging snippets from ovn-controller.
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2020-08-07T16:38:04.020Z|29250|timeval|WARN|Unreasonably long 8954ms poll interval (8895ms user, 0ms system)
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What's that mean? Is it harmless?

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2020-08-07T16:38:04.021Z|29251|timeval|WARN|context switches: 0 voluntary, 6 involuntary
2020-08-07T16:38:04.022Z|29252|poll_loop|INFO|wakeup due to [POLLIN] on fd 19 (10.6.20.91:60398<->10.6.20.86:6642) at lib/stream-fd.c:157 (99% CPU usage)
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Is this wakeup caused by changes in sb-db?
Why is ovn-controller so busy?

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2020-08-07T16:38:04.022Z|29253|reconnect|WARN|tcp:127.0.0.1:6640: connection dropped (Broken pipe)
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Connection to local ovsdb-server is dropped.
Is this caused by the timeout of inactivity probe?

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2020-08-07T16:38:04.035Z|29254|poll_loop|INFO|wakeup due to [POLLIN] on fd 20 (<->/var/run/openvswitch/br-int.mgmt) at lib/stream-fd.c:157 (99% CPU usage)
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What causes this wakeup?

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2020-08-07T16:38:04.048Z|29255|poll_loop|INFO|wakeup due to 0-ms timeout at lib/ovsdb-idl.c:5391 (99% CPU usage)
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What's this 0-ms wakeup mean?

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2020-08-07T16:38:05.022Z|29256|poll_loop|INFO|wakeup due to 962-ms timeout at lib/reconnect.c:643 (99% CPU usage)
2020-08-07T16:38:05.023Z|29257|reconnect|INFO|tcp:127.0.0.1:6640: connecting...
2020-08-07T16:38:05.041Z|29258|poll_loop|INFO|wakeup due to [POLLOUT] on fd 14 (127.0.0.1:51478<->127.0.0.1:6640) at lib/stream-fd.c:153 (99% CPU usage)
2020-08-07T16:38:05.041Z|29259|reconnect|INFO|tcp:127.0.0.1:6640: connected
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Retry to connect to local ovsdb-server. A pollout event is triggered
right after connection is established. What's poolout?

ovn-controller is taking 100% CPU now, and there is no changes in
sb-db (not busy). It seems that it's busy with local ovsdb-server
or vswitchd. I'd like to understand why ovn-controller is so busy?
All inactivity probe intervals are set to 30s.


Thanks!

Tony