Re: swap_pager: cannot allocate bio

From: Chris Ross <cross+freebsd_at_distal.com>
Date: Thu, 25 Nov 2021 05:18:05 UTC
>> On Nov 20, 2021, at 13:23, Mark Johnston <markj@freebsd.org <mailto:markj@freebsd.org>> wrote:
>> 
>> Here is a patch which tries to address the proximate cause of the
>> problem.  It would be helpful to know if it addresses the deadlocks
>> you're seeing.  I tested it lightly by putting a NUMA system under
>> memory pressure using postgres.
> 
> Thank you.  I’ve updated my stable/13 tree today, and applied this
> patch.  Build and installed a kernel, and I’ll see in a few days if the
> system has remains operational and get back to you all.

The system is still cooking along, running the job that previously was
causing it to get stuck after 48ish hours.  It’s been running more than
80 hours now, so a definite improvement.

zfs-stats reports things as stable, 80% cache hit ratio, 64GB max arc,
~85% of that currently as “adaptive target”.  If there’s anything you
would like to get from the system, data-wise, let me know.  Happy to
share, and help get this fix, or a different better fix if needed, into the
tree.

Thanks again.

                  - Chris