This is a clone of issue OCPBUGS-1427. The following is the description of the original issue:
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Description of problem:

Jump looks the worst on gcp, but looking closer Azure and AWS both jumped as well just not as high.

Disruption data indicates that the image registry on GCP was averaging around 30-40 seconds of disruption during an upgrade, until Aug 27th when it jumped to 125-135 seconds and has remained there ever since.

We see similar spikes in ingress-to-console and ingress-to-oauth. NOTE: image registry backend is also behind ingress, so all three are ingress related disruption.

https://datastudio.google.com/s/uBC4zuBFdTE

These charts show the problem on Aug 27 for registry, ingress to console, and ingress to oauth.

sdn network type appears unaffected.

Something merged Aug 26-27 that caused a significant change for anything behind ingress using ovn on gcp.