Big files Upload timeout

Good morning,

we have OwnCloud 10.11 installed via Docker+K8S+Redis+Postgres on AWS machines and with S3 storage.
Our users encounter problems when massively uploading many files, divided into various folders.
From a first analysis it seems due to timeouts on the balancer, I can’t see timeout on the owncloud logs.

How can we solve it?
Could it be due to the size of the files, perhaps unchanked or with chunk sizes that are too large?

What do you suggest I try?