On Tue, Jul 21, 2020 at 03:38:35PM +0200, Michal Hocko wrote: > On Tue 21-07-20 09:23:44, Qian Cai wrote: > > On Tue, Jul 21, 2020 at 02:17:52PM +0200, Michal Hocko wrote: > > > On Tue 21-07-20 07:44:07, Qian Cai wrote: > > > > > > > > > > > > > On Jul 21, 2020, at 7:25 AM, Michal Hocko <mho...@kernel.org> wrote: > > > > > > > > > > Are these really important? I believe I can dig that out from the bug > > > > > report but I didn't really consider that important enough. > > > > > > > > Please dig them out. We have also been running those things on > > > > “large” powerpc as well and never saw such soft-lockups. Those > > > > details may give us some clues about the actual problem. > > > > > > I strongly suspect this is not really relevant but just FYI this is > > > 16Node, 11.9TB with 1536CPUs system. > > > > Okay, we are now talking about the HPC special case. Just brain-storming > > some > > ideas here. > > > > > > 1) What about increase the soft-lockup threshold early at boot and restore > > afterwards? As far as I can tell, those soft-lockups are just a few bursts > > of > > things and then cure itself after the booting. > > Is this really better option than silencing soft lockup from the code > itself? What if the same access pattern happens later on?
It is better because it does not require a code change? Did your customers see the similar soft-lockups after booting was done?