[Clustering] Switch state resync after cluster restart.

Hi,

I was testing the cluster restart scenario with latest Be Code with He Plugin.
Tested in 3 node cluster with Stable Beryllium + Helium Plugin + JDK8 with G1GC.Tested with OVS 2.3.2.

Build used :
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Karaf distro from latest ODL stable Beryllium code

Objective of test :
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To validate the cluster restart and see if all the flows get configured in the switch.

Configuration and topology:
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i.Controllers (c1, c2 and c3) VMs are running in Dell machine say h1, each VM has 8 vcpu and 16g RAM configuration

ii. Mininet (m1, m2 and m3) VMs with ovs version 2.3.2 are running in different Dell machine say h2, each VM has 8 vcpu and 16g RAM configuration.

m1 with 5 switches (1 to 6) connected to c1
m2 with 5 switches (6 - 11) connected to c2
m3 with 5 switches (11 - 16) connected to c3

Test Steps :
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Pre-requisite: Pushed 10K flows in 15 switches(150k flows in the cluster) and config DS shows 150k flows.
Note all the 15 switches were connected and then the flows were pushed.
So Cluster has 10k flows per switch,5 switches per node.Total 15 switches,150K flows configured in the 3 node cluster.

Steps:
i. Stop all the Nodes c1,c2,c3
ii. Disconnected 15 switches connecting to Node c1,c2,c3.
iii. Connect the 15 switches to the Node c1,c2,c3.
iv. Start the Node c1,c2,c3.

Observations
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After cluster restart we see that in some switches there are less than 10K flows.Out of 15, 6 switches has 0 flows and remaining 9 switches shows 10K flows.

Attaching the logs for more clarity.

Thanks & Regards,
Saibal Roy.