Re: Status of Alder Lake support

On 2022-08-19 21:43 -0400, Alexander Motin wrote:
> Hi Kevin,
> 
> On 19.08.2022 20:50, Kevin Oberman wrote:
> > What is the current state of support for Alder Lake CPUs with a mix of 
> > "performance" and "Efficiency"?? cores. I just received my first system 
> > with such a processor and will be installing FreeBSD as soon as my SSD 
> > arrives. I have no idea what issues I might run into. (Will it even work?)
> 
> Generally they work.  I have one in my lab since they appeared, and its 
> biggest problem is UEFI console screwed by ASUS, which I partially 
> fixed.  At some BIOS versions they also broke PXE booting, but then 
> fixed it in later update.

I have an ASUS Prime Z690-P and had this issue with 13.1 and CURRENT.


> The FreeBSD scheduler still has no idea about P and E cores, just trying 
> to balance load equally based on cache topology (which is not symmetric 
> there), but it is not too bad, since cores performance is not so 
> dramatically different.

Right now I'm running 13.1 if I enable any of my E cores I get UFS corruption 
everywhere so I've had to have these disabled.  There is a ticket 
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=261169 which 
I just updated as I'm still having issues.


> hwpmc(4) also does not differentiate P and E cores, and since they have 
> different counters, it means that only few universal architectural 
> counters are usable, which are sufficient for basic profiling though.
> 
> There were some stability issues reported, but were solved by either 
> FreeBSD or BIOS update, so still not really diagnosed AFAIK.

I've run into this in my situation some BIOs updates cause constant reboots 
especially when playing video.  I also have serious audio issues with continous 
popping that I've been unable to solve there is a ticket for that as well:

  https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=263385#add_comment

I'll give CURRENT A shot again in the next day or two to see if this is all 
fixed thanks for the update!


Amar.