[LAU] performance problems after kernel/microcode update ?

david gnome at hawaii.rr.com
Fri Sep 14 08:49:31 CEST 2018

On 09/13/2018 08:05 PM, Will Godfrey wrote:
> 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.
> Is this only Intel processors that are doing this? I've been running an AMD
> Ryzen since March and had no problems at all.

You mean for the original poster, or me? I have no such problems on 
either of my systems. But my AMD isn't a Ryzen, it's a Phenom II.

David W. Jones
gnome at hawaii.rr.com
authenticity, honesty, community

More information about the Linux-audio-user mailing list