Using OpenVPN to access our remote server (with mapped drives), Houdini is the only software that's having a big problem reading/writing files to our network.

houdini.env is pretty simple and has access_method = 2 (because of redshift), I tried =0 and =1 but same problem persists.

Opening an hip file is fast, but saving it is extremely slow. A 5mb hip takes almost 1min to save.
Opening houdini with several plugins like qLib, Quixel, MOPS, etc. is extremely slow… like 3-4min to open. While before when i was physically onsite, it took 15secs.

My internet speed is fine, 500/100 mbps. Other softwares don't have this issue, only Houdini.

Is there any solution for this?

Not only me, but a few of my colleagues have the same issue.

You could try setting HOUDINI_BUFFEREDSAVE=1 and see if that helps your saving performance.

In terms of performance with a lot of otls that is kind of expected. Houdini accesses otl files a lot. It also doesn't help with some projects like MOPS (I think?) which store their otls in the expanded directory format instead of actual .otl/.hda files. This can cause performace issues as well.

MOPs has a shelf tool built-in that will collapse the HDA definitions. If you use the Updater shelf tool or the Collapse HDAs shelf tool to collapse the original definitions stored on GitHub, the startup time when loading over a network should be much better.

@romanus did you ever find a solution?
I just hit the same issue: Houdini takes >30min to save a 50MB file to a networked drive using Wireguard (VPN) remotely.
Copying the same file to the same location using Windows Explorer takes about 5 seconds.
It's only Houdini, from what I've seen. Very weird.

EDIT: Just tested with BUFFEREDSAVE = 1 and it helps immensely. >30min is now 30 seconds or so.