Re: netbsd-6: pagedaemon freeze when low on memory

[David Laight <david%l8s.co.uk@localhost>]

On Wed, Mar 06, 2013 at 06:01:50PM -0600, David Young wrote:
> > 
> > Here's another thought:  What about changing some of the VM_SLEEP calls
> > to VM_NOSLEEP, at least for the userspace-initiated syscalls?  The
> > syscalls would then fail, moving the responsibility of dealing with low
> > memory onto the userspace apps (they may be unhappy, but at least the
> > kernel will stay functional).  This change would be in addition to the
> > vmem_xalloc() wake changes you proposed (because those wake-ups may
> > never come if the system is truly running on fumes).
> 
> You could do that.  You just have to take care to handle the errors
> properly.  There are more error paths to test.  Not trying to discourage
> you, just point out the trade-offs. :-)

Possibly some of the sleeps could be interruptable (by a signal).
But that rather depends on the system calls involved.

        David

-- 
David Laight: david%l8s.co.uk@localhost