fireface 802: too much latency with pipewire

[francoisromain]

Hello Takashi, I try to use the fireface 802 on Fedora 37 (Linux 6.1.14) with pipewire (0.3.66).

Pipewire config .config/pipewire/pipewire.conf.d/10-clock-quantum.conf :

context.properties = {
        default.clock.quantum       = 256
}

The roundtrip latency measured with jack_iodelay:

new playback latency: [256, 256]
4753.261 frames     99.026 ms total roundtrip latency
extra loopback latency: 4241 frames

This 99,026ms latency makes it unsuable to play instruments.

(for comparaison : in usb the roundtrip latency is 26.123 ms)

---

I tried to follow the instructions here and modified /usr/share/wireplumber/main.lua.d/50-alsa-config.lua, alsa_monitor.rules:

  {
    matches = {
      {
        -- Matches the rme fireface
        { "device.name", "matches", "alsa_card.firewire-*"},
      },
    },
    apply_properties = {
      ["api.alsa.period-size"]   = 256,
      ["api.alsa.period-num"]    = 3,
    },
  },

But it does not change anything.

How is it possible to fix the latency?

[takaswie]

Hi,

But it does not change anything.

How is it possible to fix the latency?

In my humble opinion, it is preferable to get consultant from WirePlumber developer.

I note that when configured property, node in procfs can report the values during playback, like:

$ cat /proc/asound/Fireface802/pcm0p/sub0/hw_params 
access: MMAP_INTERLEAVED
format: S32_LE
subformat: STD
channels: 30
rate: 48000 (48000/1)
period_size: 256
buffer_size: 768

[francoisromain]

Thank you for your answer.

cat /proc/asound/Fireface802/pcm0p/sub0/hw_params
access: MMAP_INTERLEAVED
format: S32_LE
subformat: STD
channels: 30
rate: 48000 (48000/1)
period_size: 1024
buffer_size: 4096

The wireplumber config does not seem to be taken in account. I am investigating

[francoisromain]

Dou you have a custom configuration for pipewire / wireplumber?

[takaswie]

Dou you have a custom configuration for pipewire / wireplumber?

I'm sorry but I have never customized these services. I use them with default configuration.

[francoisromain]

cat /proc/asound/Fireface802/pcm0p/sub0/hw_params you sent above was done with the fireface 802 and pipewire's default?

[takaswie]

cat /proc/asound/Fireface802/pcm0p/sub0/hw_params you sent above was done with the fireface 802 and pipewire's default?

Execuse me that it is sample of output in your case. I made the output by hand.

[francoisromain]

I opened an issue here https://gitlab.freedesktop.org/pipewire/wireplumber/-/issues/433