#7603 NORM 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:  normal     |   Milestone:  8.2.0 (was Update.2)  
  Component:  kernel     |     Version:  not specified         
 Resolution:             |    Keywords:  joyride-2181:- 8.2.0:?
Next_action:  never set  |    Verified:  0                     
  Blockedby:             |    Blocking:                        
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Comment(by dsd):

 On my XO with those HAL patches applied, I am still getting a lot of
 underruns on 2.6.25 but not on 2.6.22.

 I quantified this by running tamtam and playing a drum beat (increasing
 beats per bar and randomness to about 75%) for approximately one minute,
 while logging stdout. Then I grep for how many underruns occurred. I
 repeated 3 times for each kernel.

 On 2.6.25: 99, 83, 96 (average 93 underruns)
 On 2.6.22: 17, 10, 11 (average 13 underruns)

 No other changes were made to the system, and HAL was not polling the
 battery while this was happening.

 10-15 underruns occur during standard loading of tamtam, before you are
 playing anything. Almost all of the reported underruns for 2.6.22 were
 from there, and not actually skips while audio was playing.

-- 
Ticket URL: <http://dev.laptop.org/ticket/7603#comment:17>
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