Only 10-20 MiB/s upload on 1Gbit LAN

I’m getting about 10 to 20 MiB/s upload speeds on my 1Gbit LAN (when uploading through the web interface). Which seem a bit low.
Transferring to a windows share on the same server and the same disks I can easily reach the bandwidth limit of my LAN, about 115 MiB/s.

What kind of max upload speeds are others getting on local or other 1Gbit+ connections?

Running top on the server I can see that PHP FPM processes handling the upload are using a full CPU core (with everything else idle). So it seems to be CPU limited. (And I do not have any encryption in Nextcloud enabled.)

Is it normal for uploads to be CPU limited?

(Downloads from Nextcloud are going without problem at bandwidth limit.)

I think the problem is “remote.php” and/or WebDAV. Perhaps you can test file upload from your windows-client with file explorer and webdav to your Nextcloud and in comparison to another webdav space. I think it also differ from file size and number of files.

I think Nextcloud uses in the web interface to often webdav mechanismen and not ajax (XMLHttpRequest?) . But sorry i am not a programmer.