Re: Poor USB performance on ASUS 520 motherboard (no IRQ?)

[Daniel O'Connor via freebsd-stable]

> On 24 Nov 2021, at 17:24, Daniel O'Connor <dar...@dons.net.au> wrote:
> I've tried updating the BIOS and tested FreeBSD 12 (same as the Gigabyte) and 
> FreeBSD 13 with no change.
> 
> One thing I did notice is this dmesg output:
> xhci0: <XHCI (generic) USB 3.0 controller> mem 0xfcfa0000-0xfcfa7fff at 
> device 0.0 on pci1
> xhci0: 32 bytes context size, 64-bit DMAxhci1: <XHCI (generic) USB 3.0 
> controller
> ...
> xhci1: <XHCI (generic) USB 3.0 controller> mem 0xfcb00000-0xfcbfffff at 
> device 0.3 on pci7
> xhci1: 64 bytes context size, 64-bit DMA
> ..
> xhci2: <XHCI (generic) USB 3.0 controller> mem 0xfca00000-0xfcafffff at 
> device 0.4 on pci7
> xhci2: 64 bytes context size, 64-bit DMA

It seems this is a bit of a red herring as vmstat -i does show it getting IRQs, 
not sure why they don't show up in dmesg though. Some discussion on IRC 
suggests it is because the system has no legacy PCI IRQs.

However on the system in question the IRQ rate tops out at 1kHz and on the 
other it is 8kHz which I think explains my problem.

I'm going to have a look for BIOS settings today but getting a bit desperate 
for ideas..

--
Daniel O'Connor
"The nice thing about standards is that there
are so many of them to choose from."
 -- Andrew Tanenbaum