Booting from USB painfully slow

[ncx]

Hello,

I recently installed Proxmox on a USB 3.2 Gen 2 stick (Kingston DataTraveler Max). The USB is rated for 1000/900 MB/s. I noticed that booting off the USB takes a long time to fully load the kernel and the initrd. Loading the kernel takes about a minute and "Loading initial ramdisk ..." takes about 2-3 minutes. Why is it so slow? I know it is not so recommended to run Proxmox off a USB drive but anyway, I need to know why it takes so much time to load the kernel and the initrd on such a fast USB disk. Once they are fully loaded, systemd boots very quickly and VMs performance is great. Is there a way to speed up the boot process so I can utilize my USB speed properly?

# systemd-analyze
Startup finished in 3.416s (kernel) + 19.734s (userspace) = 23.150s
graphical.target reached after 19.714s in userspace.

 

[Tymofii]

It's not about Proxmox. But if you manage it - please, let me know how.
I have the same issue with the HP P900 2TB (USB 3.2 Gen 2). It boots very slowly (minutes), but it works fast after the system is initiated. The same on different distros (KUbuntu 24.04, 24.10, KDE Neon). And I tried two different laptops. On the other side, my old Samsung T5 500G (USB 3.1) boots fast.