On Mon, Oct 14, 2019 at 8:20 AM <[email protected]> wrote:
> From: Numan Siddique <[email protected]> > > The commit [1] force drops all connections when the db read/write status > changes. > Prior to the commit [1], when there was read/write status change, the > existing > jsonrpc sessions with 'db_change_aware' set to true, were not updated with > the > changed 'read_only' value. If the db status was changed to 'standby', the > existing > clients could still write to the db. > > In the case of pacemaker OVN HA, OVN OCF script 'start' action starts the > ovsdb-servers in read-only state and later, it sets to read-write in the > 'promote' action. We have observed that if some ovn-controllers connect to > the SB ovsdb-server (in read-only state) just before the 'promote' action, > the connection is not reset all the times and these ovn-controllers remain > connected > to the SB ovsdb-server in read-only state all the time. Even though > the commit [1] calls 'ovsdb_jsonrpc_server_reconnect()' with 'forced' flag > set to true when the db read/write status changes, somehow the FSM misses > resetting > the connections of these ovn-controllers. > > I think this needs to be addressed in the FSM. This patch doesn't address > this FSM issue. Instead it changes the behavior of > 'ovsdb_jsonrpc_server_set_read_only()' > by setting the 'read_only' flag of all the jsonrpc sessions instead of > forcefully > resetting the connection. > > I think there is no need to reset the connection. In large scale production > deployements with OVN, this results in unnecessary waste of CPU cycles as > ovn-controllers > will have to connect twice - once during 'start' action and again during > 'promote'. > > [1] - 2a9679e3b2c6("ovsdb-server: drop all connections on read/write > status change") > > Acked-by: Dumitru Ceara <[email protected]> > Signed-off-by: Numan Siddique <[email protected]> > --- > > Thanks Numan. Is this the root cause of the ovn-controller transaction failure you mentioned at last OVN meeting? _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
