Description of problem:
While scaling up to 450 UDNs i.e 450 namespaces each with its own UDN takes a long time. The time is mostly spent to add logical routes and logical switches to each node. To get to 450 UDNs it takes about 9h. For baseline it takes 10mins to scale up to 450 namespaces without any UDNs

Version-Release number of selected component (if applicable):

4.18.0-0.nightly-2024-09-30-051028

How reproducible:

Always

Steps to Reproduce:

1. Run a client-server workload with 10 pods per namespace using kube-burner at 20 QPS

2. Deploy with 450 namespaces each with its own UDN

3. Check how much time it takes for all the pods to get primary network ip (UDN)

Actual results:

Creation of UDNs one after another takes a long time. It seems there is some wait as the creation of CRDs for all 450 namespace is done at the very start

Expected results:

A much quicker deployment to networks