Laptop exhibits erratic responsiveness

[Konstantin Belousov]

On Mon, Nov 30, 2020 at 01:22:45PM -0800, David Wolfskill wrote:
> On Mon, Nov 30, 2020 at 11:03:29PM +0200, Konstantin Belousov wrote:
> > ...
> > > I suppose I will be commenting out that DIAGNOSTIC option now.... :-}
> > 
> > Try to just set debug.vmem_check to 0 and see if it helps.
> > ...
> 
> OK; I rebooted the new(er) laptop with the previous kernel (that was
> built with "option DIAGNOSTIC") and reproduced the issue:
> 
> --- albert.catwhisker.org ping statistics ---
> 37 packets transmitted, 37 packets received, 0.0% packet loss
> round-trip min/avg/max/stddev = 0.451/13.832/178.867/41.904 ms
> 
> Then:
> 
> g1-216(13.0-C)[2] sudo sysctl debug.vmem_check
> Password:
> debug.vmem_check: 1
> g1-216(13.0-C)[3] sudo sysctl debug.vmem_check=0
> debug.vmem_check: 1 -> 0
> 
> On recheck:
> 
> --- albert.catwhisker.org ping statistics ---
> 60 packets transmitted, 60 packets received, 0.0% packet loss
> round-trip min/avg/max/stddev = 0.411/0.551/1.051/0.084 ms
> 
> which looks pretty good to me.

I wanted to change the default some time ago.  Do not remember why it did
not happen.