RE: Sys-usb read/write bottleneck

I have an external drive with a r/w speed of up to 2000 MB/s.
Hardware USB ports support up to 10 Gbit/s.

The best I’m able to get in r/w speeds are 198 MB/s.
I’m benchmarking in a disposable qube using Gnome Disks.

Sys-usb is a disposable.
I’ve tested increasing the threads to up 6, increasing the ram to up to 8mb, and tested each kernel.

The only thing that made a difference was adding sys-usb to memory balancing (went form 180->198 MB/s).

I’m running the latest 4.1.2.

I’ve tested the drive on other computers, and am able to get 1000+ MB/s.
I’ve tested another drive with a 1200 MB/s speed, but still could not get beyond 198 MB/s r/w running it thru sys-usb.

I can rule out the drive and the cables.

What do you think might be causing the bottleneck?

Edit: I tested the drive on a throwaway install on a direct connection, without sys-usb. I was able to get expected speeds.
Somewhere there’s a chokepoint in sys-usb.
Anyone have a fix?

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I can’t currently provide specific data points but I have also encountered slower block storage read/write rates in Qubes 4.1.1. I just figured it was due to the different layers of virtualization and other Xen-related abstractions, so I also would be interested in hearing from anyone else if they have encountered this too, and any tips.