Re: the stuttering regression in 7.0: should I have done something different

[Thomas Gleixner]

Hi!

On Fri, May 15 2026 at 19:51, John Paul Adrian Glaubitz wrote:
> On Fri, 2026-05-15 at 17:35 +0200, Thomas Gleixner wrote:
>> > Thank you again for the debugging guidance and for the feedback on my 
>> > original patch addressing the timer starvation issue. It was a pleasure 
>> > contributing to the resolution.
>> 
>> Thank you for going through the hassle of chasing it down and providing
>> the debug data to analyze it.
>> 
>> I'm still puzzled how this went unnoticed for almost two decades:
>> 
>>    112f48716d9f ("[SPARC64]: Add clocksource/clockevents support.")
>
> My suspicion is that it was previously visible only in certain edge cases,
> in particular on machines with many cores and high load.
>
> Case in point: In the past, SPARC LDOMs with lots of virtual CPUs could
> crash in rares cases when building packages such as GCC or LLVM and running
> their testsuites.

I assume those occasional failures did not leave conclusive hints around.

> I don't know if Tony's patch fixes this long-time issue that we have observed
> in the past on Debian's buildds, but I think that the chances aren't too bad.

Good luck!

> Thanks to both of you for hunting this down!

For some stupid reasons I like such puzzles :)