#7603 HIGH 8.2.0 (: 2.6.25 audio performance regression

[Zarro Boogs per Child]

#7603: 2.6.25 audio performance regression
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   Reporter:  dsd       |       Owner:  dilinger                            
       Type:  defect    |      Status:  new                                 
   Priority:  high      |   Milestone:  8.2.0 (was Update.2)                
  Component:  kernel    |     Version:  not specified                       
 Resolution:            |    Keywords:  joyride-2181:- 8.2.0:? blocks?:8.2.0
Next_action:  diagnose  |    Verified:  0                                   
  Blockedby:            |    Blocking:                                      
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Comment(by veplaini):

 Replying to [comment:31 dsaxena]:
 > I did some Googling around of "ALSA underrun scheduler" and found
 https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/190754 and
 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/188226. By enabling
 group scheduling and forcing all applications to be in one group by
 disabling per-UID scheduling groups, I can run TamTamMini for 10+ minutes
 with an average of < 1 underrun per second.
 >
 > I also think that we should put the call to SCHED_RR back into Clooper.
 It looks to me like this got dropped at some point and my (rudimentary so
 far) testing shows further improvement with
 > this scheduling policy enabled (I've gone 10 minutes with zero underruns
 at one point)
 >
 > Patches will follow.
 >
  This sounds like an excellent idea. There is a wealth of knowledge out
 there for
 realtime audio scheduler solutions which we could tap into. Should we
 patch csound (I am thinking here InOut/rtalsa.c) to include a SCHED_RR
 call too?
 Thanks.

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Ticket URL: <http://dev.laptop.org/ticket/7603#comment:33>
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