[pulseaudio-discuss] Virtual audio cable - high cpu usage

[Renaud GHIA]

Thank you for the tip.
Now I am sure that resampling does not apply (see below).
But unfortunately pulseaudio always consumes 30% of one CPU core!

Renaud

driver: <protocol-native.c>
flags:
state: RUNNING
source: 8 <VACmic>
volume: front-left: 65536 / 100% / 0.00 dB,   front-right: 65536 / 100% /
0.00 dB
       balance 0.00
muted: no
current latency: 0.50 ms
requested latency: 2000.00 ms
sample spec: s16le 2ch 44100Hz
channel map: front-left,front-right
            Stereo
resample method: (null)
owner module: 6
client: 29 <Lavf58.20.100>
properties:
media.name = "record"
application.name = "Lavf58.20.100"
native-protocol.peer = "UNIX socket client"
native-protocol.version = "32"
application.process.id = "18295"
application.process.user = "vagrant"
application.process.host = "debian10.localdomain"
application.process.binary = "ffmpeg"
application.language = "C"
window.x11.display = ":0"
application.process.machine_id = "c79df160d01f4c7780e6da0aaf5515c3"
application.process.session_id = "8"
module-stream-restore.id = "source-output-by-application-name:Lavf58.20.100"

Le mer. 3 févr. 2021 à 21:04, Sean Greenslade <sean at seangreenslade.com> a
écrit :

> On Tue, Feb 02, 2021 at 10:40:51AM +0100, Renaud GHIA wrote:
> > Hi,
> >
> > Below the result of the command "pacmd list".
> > Here without any change of resampling method.
>
> This part here shows your ffmpeg client:
>
> >     index: 1
> > driver: <protocol-native.c>
> > flags:
> > state: RUNNING
> > source: 2 <VACmic>
> > volume: front-left: 65536 / 100% / 0.00 dB,   front-right: 65536 / 100% /
> > 0.00 dB
> >        balance 0.00
> > muted: no
> > current latency: 0.50 ms
> > requested latency: 2000.00 ms
> > sample spec: s16le 2ch 48000Hz
> > channel map: front-left,front-right
> >             Stereo
> > resample method: speex-float-1
>
> It seems like ffmpeg is requesting 48 kHz audio, so pulse is forced to
> resample. If possible, can you try running your ffmpeg process with the
> flag "-sample_rate 44100" and see if that reduces the CPU usage?
>
> Everything else in your pulse chain is 44.1 kHz, so with that change
> there should be no resampling at all.
>
> --Sean
>
> _______________________________________________
> pulseaudio-discuss mailing list
> pulseaudio-discuss at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/pulseaudio-discuss/attachments/20210203/9062d5f4/attachment.htm>