Viscosity very slow on Mac M1

[mlove]

Sometime between July and now the speed of my Viscosity client became very slow (from 50Mbps to < 1Mbps). I've been trying to diagnose this, originally thinking it was a problem with our OpenVPN server. I installed TunnelBlick and I'm getting 50Mbps with it, but using the exact same config in Viscosity 1.11.3 and 1.11.4.b1 gives me less than a megabit.

I'm not sure when this changed because I've only been using it for shell access for the last few months until recently had to upload and download files.

I'm currently running Viscosity 1.11.4b1, on a MacBook Pro M1 with Mac OS 15.0.1. Our server is OpenVPN 2.6.12, running a tap bridge over UDP using AES-256-GCM encryption.

Any help would be appreciated!

[James]

Hi mlove,

Thanks for the report. We're aware of this one, and actively working on it. It only affects TAP (bridged) connections on macOS 15.0.1 and 15.1, TUN (routed) connections are not affected, nor are earlier versions of macOS.

It's related to Apple blocking access to the APIs necessary for Viscosity's Virtual Ethernet driver as discussed in this forum post:
viewtopic.php?t=3382#p10450

As mentioned in that post, Viscosity will be automatically falling back to the "Fake Ethernet" backup TAP driver, however performance with this can be very poor with many setups. We anticipate on having a beta version out later this week that significantly improves Fake Ethernet performance, so please keep an eye out for that:
https://www.sparklabs.com/support/kb/ar ... -versions/

We're also aiming to have another update out sometime in the next few weeks that restores Viscosity's Virtual Ethernet driver support as well.

Cheers,
James

[mlove]

Heck, I didn't look at that post because I didn't think I was using that driver!

Thanks!

[James]

Just a heads up that we've released an updated beta version (1.11.4b2) that should improve performance on macOS 15.0.1+. Please give it a try and let us know if you still encounter any poor TAP performance or issues.
https://www.sparklabs.com/support/kb/ar ... -versions/

Cheers,
James