Re: ... was killed: a thread waited too long to allocate a page [actually: was killed: failed to reclaim memory problem]

--On 01 February 2024 08:30 -0800 Mark Millard <marklmi@yahoo.com> wrote:
> [snip]
>
> One direction of control is . . .
>
> What do you have for ( copied from my /boot/loader.conf ):
>
>#
># Delay when persistent low free RAM leads to
># Out Of Memory killing of processes:
> vm.pageout_oom_seq=120

loader.conf is empty - it's a pretty stock / out the box install.

> The default is 12 (last I knew, anyway).

Yes, default is 12 here.

> The 120 figure has allowed me and others to do buildworld,
> buildkernel, and poudriere bulk runs on small arm boards
> using all cores that otherwise got "failed to reclaim
> memory" (to use the modern, improved [not misleading]
> message text). Similarly for others that had other kinds
> of contexts that got the message.
>
> (The units for the 120 are not time units: more like a
> number of (re)tries to gain at least a target amount of
> Free RAM before failure handling starts. The comment
> wording is based on a consequence of the assignment.)
>
> The 120 is not a maximum, just a figure that has proved
> useful in various contexts.
>
> But see the notes below based as well.

Thanks for the notes. I think I can reproduce this (but it's painful to do 
- as is pretty much any production server killing all it's procs) so I'll 
wait until next run. I've set the vm.pageout_oom_seq=120 if only because 
it's a runtime option (no reboot).

It's been many, many years since I had to do anything with default arc 
sizing on FreeBSD (thankfully) - something I wouldn't want to really do 
again for such a 'simple' machine. I've noted the change here - and we'll 
see how it goes.

> That 24G+ of wired meant that only 8GiBytes- were
> available everything else. Avoiding that by limiting
> the ARC (tuning ZFS) or adjusting how the work load
> is spread over time or some combination also looks
> appropriate.

tbh - 8GiB is probably more than enough for what's running on that machine 
(very little) - but I take your point.

Cheers,

-Karl