Ingress sync delay when creating 1000+ ingresses simultaneously

When creating a large number of ingresses (~1000+) at the same time on EKS v1.31 with nginx-ingress-controller v1.12.4, I noticed inconsistent sync behavior: • Some ingresses sync immediately and get the LoadBalancer IP. • Others take 8–10 minutes before they are scheduled for sync and updated with the LB IP.

Example event log from delayed ingress:

Normal Sync 7m47s nginx-ingress-controller Scheduled for sync

Steps to Reproduce 1. Deploy an nginx-ingress-controller (v1.12.4) on EKS v1.31. 2. Create ~1000 ingress resources simultaneously. 3. Observe ingress status updates in kubectl describe ingress.

Expected Behavior

All ingresses should sync and receive the LoadBalancer IP within a reasonable timeframe (a few seconds to 1–2 minutes).

Actual Behavior

A subset of ingresses takes 8–10 minutes to sync and become available.

Environment • Kubernetes version: 1.31 (EKS) • Nginx ingress controller: 1.12.4 • Number of ingresses created: ~1000+ simultaneously

Questions • Is this behavior expected due to configuration or scaling limits? • Are there any known limitations when creating thousands of ingresses at once? • Is there a recommended configuration tweak (e.g., worker tuning, queue size, resync period) to avoid this delay?