We've been experiencing this issue for a while now and have fixed it several times but it seems we are fixing it on accident, as we don't know the root cause and therefore how to fix it. When an end user tries to download a file from WebDocs it is extremely slow. A 150 MB document takes anywhere from 45 minutes to 2 hours to download. We have our web service on an AS/400 and our documents are being shared over NFS on a virtualized Windows 2019 Server. When we try to do a document transfer over SMB it works just fine, but doing the transfer over NFS is still very slow. If we put a document on the AS/400 itself then the transfer behaves normally, but the same document over NFS is too slow for any of our end users. We've rebuilt the NFS, made an exception in Windows Firewall for our NFS, uninstalled Windows updates. These things would temporarily fix the issue, but then a week to a month later the same issue would return, so we're obviously not hitting the core issue. 

Has anyone else experienced this issue and if so, how did you go about fixing it? We're trying to migrate our file share to a Cohesity drive but haven't been able to successfully mount it yet, so until then we need to get our Windows Server up and running. We're also trying to move off of the AS/400 but that project is above my pay grade.

Any help is greatly appreciated.