[LAU] performance problems after kernel/microcode update ?

[Will Godfrey]

On Thu, 13 Sep 2018 15:48:11 -1000
"David W. Jones" <gnome at hawaii.rr.com> wrote:

>On September 13, 2018 1:13:12 PM HST, Tim <termtech at rogers.com> wrote:
>> 
>> 
>> On 09/13/2018 05:26 PM, Niklas Reppel wrote:  
>> > Hi,
>> > 
>> > i recently updated my Arch linux system, to to the following  
>> version:  
>> > 
>> > Linux 4.18.6-arch1-1-ARCH #1 SMP PREEMPT
>> > 
>> > Afterwards, i noticed that something has changed regarding the  
>> realtime   
>> > permissions
>> > and that i had to install a new package called  
>> 'realtime-priviliges',   
>> > which i never needed before,
>> > and subsequently add my main user to the 'realtime' group.
>> > 
>> > In that wake, i updated the processor microcode, which i didn't use  
>> at   
>> > all before (there always was some
>> > error message during bootup, but nothing else).
>> > 
>> > After being able to start JACK in realtime again, i felt that there  
>> was   
>> > a significant loss of performance.
>> > Things that didn't cause any dropouts before now start to crackle  
>> and   
>> > gristle (as a sidenote, i mostly
>> > use SuperCollider to make sound).
>> > 
>> > Also, and this puzzled me especially, there were dropouts, but no  
>> XRuns   
>> > ... normally, when i push the
>> > system to the limits, i get XRuns, that'd be expected. But now, it's  
>>   
>> > dropouts without, and they start way
>> > earlier.
>> > 
>> > My machine has an Intel(R) Core(TM) i7-4600U CPU @ 2.10GHz Processor  
>> if   
>> > that info is of user for anyone ...
>> > 
>> > Anybody else noticed something like that recently ?
>> > 
>> > Best,
>> > nik
>> >   
>> 
>> Hello, I always reply when I hear of crackles, pops, and dropouts
>>  because it took me several months to figure out my problem with that.
>> Maybe it will help.
>> 
>> Here is the latest time I replied, a month ago, please scroll down:
>> 
>> http://linux-audio.4202.n7.nabble.com/M-Audio-Fast-Track-Pro-unreliable-distorted-recording-td89125i20.html#a106829
>> 
>> Long story short: Try running with only one processor core active.
>> 
>> It completely cured my problem, and another user's as well.
>> In my case the device is a PCI M-Audio delta1010, and in the
>>   other user's case it was a similar ice1712-based card.
>> However in the above Fast-Track-Pro case, that's USB and we
>>   don't yet know if the trick solved that user's problem...
>> 
>> Be patient: If the number of CPU cores is the cause it may take
>>   several minutes for the crackling to appear since I believe what
>>   happens is that some low-level 'counters/pointers' which should
>>   always be in sync slowly approach and 'pass' each other, and that's
>>   when the noise occurs.
>> 
>> In my case the very same symptom occurred in Windows.
>> That proved beyond doubt that it was a hardware issue.
>> 
>> Hope that helps.
>> Tim.  
>
>While I, on the other hand, use all cores (real and hyperthread) on my i7 with no crackles or distorted recordings and such at all. Same for the 4 real cores on my AMD desktop system.
>
>In my opinion, most PC motherboards weren't designed with any audio thought beyond including an on-board audio chip.
>
>--
>David W. Jones
>gnome at hawaii.rr.com
>authenticity, honesty, community
>http://dancingtreefrog.com
>
>Sent from my Android device with F/LOSS K-9 Mail.

Is this only Intel processors that are doing this? I've been running an AMD
Ryzen since March and had no problems at all.

-- 
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.