On 30 July 2025 21:36:00 CEST, "M. Armsby" m.armsby@gmx.de wrote:
The new ALSAfirewire drivers are very good. Well done to everyone who worked on them!
Today I tested brand new CachyOS with xfce desktop kernel 6.15 Initial Pipewire test showed RTT 98ms at 64/44100 so I uninstalled all traces of Pipewire and installed PulseAudio and Jack2 instead. I first tested ALSA direct from Reaper with Echo Audiofire4, Pianoteq and the RTT was as expected around 8ms (no 90ms) Then Jack2 with ALSAfirewire. The result was very similar and around 2% less rtCPU usage but a few X-runs on page refresh. I then set CPU to balanced and Jack failed with hundreds of X-runs whereas your wonderful ALSAfirewire alone continued with no X-runs :)
So you don't need to re-invent anything and there is nothing reasonable about 90ms delay. ALSAfirewire is working fine as long Pipewire isn't involved.
Please fix the Pipewire problem as now nearly all distros are issued with it and everyone is blaming ALSAfirewire stack! This madness should be stopped don't you agree?
Please.
Thanks Martin Armsby
-------- Original Message -------- From: Takashi Sakamoto o-takashi@sakamocchi.jp Sent: 24 July 2025 16:38:13 CEST To: m.armsby@gmx.de Cc: alsa-devel@alsa-project.org Subject: Re: ALSAfirewire broken
The 90ms delay is reasonable..., depending on the PCM buffer configuration.
At present, all of drivers in ALSA firewire stack works with such delay due to queued initial packet. Therefore PipeWire computes the delay as expected. We would need to reeinvent the packet streaming engine if reducing the delay.
@wtaymans Wim Taymans and some guest programmers found a simple workaround to bypass the 90ms delay:
monitor.alsa.rules = [ { matches = [ { node.name = "alsa_output.firewire-0x000a35003926b6db.pro-output-0" } ] actions = { update-props = { api.alsa.period-num = 3 } } } ]
The communication from DAW to pure ALSAfirewire is not burdened with 90ms so please change the pins or whatever pipewire is using, so that it can avoid the 90ms like a DAW does when communicating directly to ALSAfirewire driver. It must be obvious and easy to see in comparison and thus fix.
ALSAfirewire RTT = 10ms Pipewire-Firewire RTT = 10 + 90ms
Please, many professionals are waiting for this fix which will boost Linux up to professional level.
Thanks
-- Martin Armsby