ALSA hi-res timer not found until Jack is run

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ALSA hi-res timer not found until Jack is run

Tim-2
On 4/14/19 5:42 PM, Tim wrote:
 > Hi list.
 > When I fist boot each day, this is what I get,
 >   no hi-res timer:
 >
 > cat /proc/asound/timers
 > G0: system timer : 4000.000us (10000000 ticks)
 > P0-0-0: PCM playback 0-0-0 : SLAVE
 > P0-0-1: PCM capture 0-0-1 : SLAVE
 > P2-0-1: PCM capture 2-0-1 : SLAVE
 >
 >
 > But after I start Jack, I get this:
 >
 > cat /proc/asound/timers
 > G0: system timer : 4000.000us (10000000 ticks)
 > G3: HR timer : 0.001us (1000000000 ticks)
 >    Client sequencer queue -1 : running  <<< Jack I believe
 > P0-0-0: PCM playback 0-0-0 : SLAVE
 > P0-0-1: PCM capture 0-0-1 : SLAVE
 > P2-0-1: PCM capture 2-0-1 : SLAVE
 >
 >
 > But curiously, after I *quit* Jack and Jack dbus
 >   and ensure they are not running, I still get this:
 >
 > cat /proc/asound/timers
 > G0: system timer : 4000.000us (10000000 ticks)
 > G3: HR timer : 0.001us (1000000000 ticks)
 > P0-0-0: PCM playback 0-0-0 : SLAVE
 > P0-0-1: PCM capture 0-0-1 : SLAVE
 > P2-0-1: PCM capture 2-0-1 : SLAVE
 >
 > Notice the hi-res timer is now still available.
 > What's happening?
 > I can only see that Jack uses pcm and seq but no timers.
 > Seems by virtue of Jack using pcm/seq, ALSA loads a module
 >   or something.

Ah, that would be snd_hrtimer I suppose.

Module                  Size  Used by
snd_hrtimer            16384  1   <<< Jack

It's been a while since I had to force a module to load or
  think about these things. Let's see, how to do it these days...
And how to do it through our app.
Could it be considered a bug that it is not available?

Sorry for the noise.
Tim.

 >
 > How can I ensure that the hi-res timer is available
 >   always from boot up? Must I manually load a module?
 > Most *importantly*, can I do this through our application
 >   software so that users do not have to load a module?
 >
 > Thanks.
 > Tim.
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