Sudden grow of memory in "Laundry" state

[Rozhuk Ivan]

On Mon, 5 Nov 2018 15:04:38 -0800
Mark Millard <marklmi at yahoo.com> wrote:

> > Mem: 50M Active, 3331M Inact, 192M Laundry, 362M Wired, 208M Buf,
> > 212M Free Swap: 16G Total, 151M Used, 16G Free  
> 
> Without extra evidence, do not beleive the "out of swap space"
> part of "killed: out of swap space".
> 
> But it turns out there is a tunable setting to control how many
> tries at freeing memory before kills happen: so, indirectly,
> how "long" before the kills will start under sustained low
> free RAM conditions.
> 

I undestand that real kill reason is not enough free RAM, not swap.


> The default vm.pageout_oom_seq=12 can be increased
> to increase how long a low-free-RAM condition is tolerated.
> I assign vm.pageout_oom_seq in /etc/sysctl.conf --but that may
> not be the best for your context.

I do not undestand why system keep that crap in my RAM (making big disk cache)
and does not return it back, and prefer to move some other process/mem to swap.
I want limit disk cache size / durty pages via sysctl, or let it scale to all free mem but if some app need memory - it can take from that cache.
For now I see that system does not like to give to apps that mem.

FreeBSD has worst mem system design for user purposes, linux and windiws mush better.
Only FreeBSD may stick because all 32GB mem used by something (not user processes) and try to start swapping.
I never use swap with windows and linux, I always know who eat my mem.

I try many sysctl tunings but without success - disk cache/durty pages grow and system freeze (if swap is off).
I see some where in past some patch to VM system that more active free mem, but lost link and not try it. :(
Laundary and some other improvenets from FreeBSD 10 to 11.2 is big step, but still have no confort in use.