svn commit: r338507 - in head/sys: sys vm

[Mark Johnston]

On Fri, Sep 07, 2018 at 09:50:10AM +0200, Alexander Leidinger wrote:
> Quoting Mark Johnston <markj at freebsd.org> (from Thu, 6 Sep 2018  
> 19:28:53 +0000 (UTC)):
> 
> > Author: markj
> > Date: Thu Sep  6 19:28:52 2018
> > New Revision: 338507
> > URL: https://svnweb.freebsd.org/changeset/base/338507
> >
> > Log:
> >   Avoid resource deadlocks when one domain has exhausted its memory. Attempt
> >   other allowed domains if the requested domain is below the minimum paging
> >   threshold.  Block in fork only if all domains available to the forking
> >   thread are below the severe threshold rather than any.
> 
> Could the problem you fixed manifest itself in e.g. a hanging system  
> due to not enough memory free despite top displaying a lot of memory  
> free (let's assume 2 memory domains and several gigs in both)?

Yes.

> I have a system which never went below a specific amount of memory  
> (before the fix of the no-rebalancing bug in the scheduler) if NUMA  
> was enabled. With NUMA disabled I see much less memory free. I haven't  
> tried NUMA after the fix of the scheduler, but would give it a try  
> again if you think this could be a manifestation of the problem.

I think it's worth trying again.