ArchQ kernel

[sbilotta]

the installation ISO should contain an "optimized real-time kernel (EVL), the system operates at a high tick rate (441 / 396.9 / 352.8 kHz). As a result, you’ll experience sound quality similar to upsampling from a 44.1 kHz sample rate."

However, once installed, I don't see such a kernel.

Can you please point out to that EVL kernel (within the ArchQ ISO, or elsewhere) so that I can verify and install it?

Thanks

[sam0402]

Please log in to the ArchQ server via SSH, then run the config command and select Kernel → Install.
You will see the EVL kernels listed there.

[sbilotta]

Thanks. It would seem that the EVL kernel is missing both iwlwifi (WiFi) and the built-in ethernet driver (e1000e or similar). The only way to get network on this kernel (without recompiling) is to use that USB ethernet adapter.
Can you confirm this, or am I mistaken?

[sam0402]

Only the following are supported:
Ethernet: Intel e100, e1000, 82575/82576(IGB), I225-LM/I225-V (IGC), Realtek RTL8125/8127/8129/8130/8139/8111/8168/8411
USB Ethernet: Realtek RTL8152/8153/8156, ASIX AX88179/178A

[sbilotta]

and can ArchQ (with EVL) be configured as a Roon server (not Bridge)?

[sam0402]

'config' comand -> Advence config -> Server -> Roon

[sbilotta]

Thanks.
Is it correct to say that, while ArchQ does offer "Roon Server" as an install option, but it hasn't been tuned or tested for running the full Roon Server stack under the EVL kernel in the way that MPD and LMS have?
In other words, CPU isolation for multi-core systems is only set up for MPD, LMS, and Squeezelite — not Roon?

With the EVL real-time kernel (6.18.7-6-Q352WU), RoonAppliance exits with exit code 137 (SIGKILL) after exactly ~18-20 seconds, every time, in a continuous loop. RoonServer and RoonGoer start fine — only RoonAppliance fails.
Running RoonAppliance directly produces only 3 lines of output before silently exiting:

[Sentry] Initialized for RoonServer (appliance)...
aac_fixed decoder found...
has mp3float: 1, aac_fixed: 1
No crash logs, no kernel OOM messages, no dmesg entries. The process just dies.

Can you help me understand the root cause of this behaviour and advise whether Roon Server with EVL is even beneficial?

Thanks

[sam0402]

ArchQ is primarily optimized and fine-tuned for LMS and MPD. Support for Roon dates back to two years ago; if it cannot function properly, support for it will be discontinued. Currently, only Squeezelite has been optimized for EVL. However, the EVL kernel still provides sound quality improvements even for playback software that has not been adapted to EVL.