Re: Break 2.4 VM in five easy steps

[Marcelo Tosatti]

On Thu, 7 Jun 2001, Mike Galbraith wrote:

> On 6 Jun 2001, Eric W. Biederman wrote:
> 
> > Mike Galbraith <[e-mail]> writes:
> >
> > > > If you could confirm this by calling swapoff sometime other than at
> > > > reboot time.  That might help.  Say by running top on the console.
> > >
> > > The thing goes comatose here too. SCHED_RR vmstat doesn't run, console
> > > switch is nogo...
> > >
> > > After running his memory hog, swapoff took 18 seconds.  I hacked a
> > > bleeder valve for dead swap pages, and it dropped to 4 seconds.. still
> > > utterly comatose for those 4 seconds though.
> >
> > At the top of the while(1) loop in try_to_unuse what happens if you put in.
> > if (need_resched) schedule();
> > It should be outside all of the locks.  It might just be a matter of everything
> > serializing on the SMP locks, and the kernel refusing to preempt itself.
> 
> That did it.

What about including this workaround in the kernel ?