From 64592da65e3cf28d0d3d81caf664e841093cd22d Mon Sep 17 00:00:00 2001

From: Renat Nurgaliyev <impleman@gmail.com>

Date: Tue, 10 Nov 2020 15:23:37 +0100

Subject: [PATCH] northd: Don't poll ovsdb before the connection is fully

 established

Set initial SB and NB DBs probe interval to 0 to avoid connection

flapping.

Before configured in northd_probe_interval value is actually applied

to southbound and northbound database connections, both connections

must be fully established, otherwise ovnnb_db_run() will return

without retrieving configuration data from northbound DB. In cases

when southbound database is big enough, default interval of 5 seconds

will kill and retry the connection before it is fully established, no

matter what is set in northd_probe_interval. Client reconnect will

cause even more load to ovsdb-server and cause cascade effect, so

northd can never stabilise. We have more than 2000 ports in our lab,

and northd could not start before this patch, holding at 100% CPU

utilisation both itself and ovsdb-server.

After connections are established, any value in northd_probe_interval,

or default DEFAULT_PROBE_INTERVAL_MSEC is applied correctly.

Signed-off-by: Renat Nurgaliyev <impleman@gmail.com>

Signed-off-by: Numan Siddique <numans@ovn.org>

(cherry-picked from master commit 1e59feea933610b28fd4442243162ce35595cfee)

---

 northd/ovn-northd.c | 4 ++--

 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c

index ce291ecb0..a158a73a7 100644

--- a/northd/ovn-northd.c

+++ b/northd/ovn-northd.c

@@ -100,8 +100,8 @@ static struct eth_addr svc_monitor_mac_ea;

 /* Default probe interval for NB and SB DB connections. */

 #define DEFAULT_PROBE_INTERVAL_MSEC 5000

-static int northd_probe_interval_nb = DEFAULT_PROBE_INTERVAL_MSEC;

-static int northd_probe_interval_sb = DEFAULT_PROBE_INTERVAL_MSEC;

+static int northd_probe_interval_nb = 0;

+static int northd_probe_interval_sb = 0;

 #define MAX_OVN_TAGS 4096

-- 

2.28.0