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List:       freebsd-hackers
Subject:    Re: idprio
From:       Terry Lambert <tlambert2 () mindspring ! com>
Date:       2002-03-31 21:26:22
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Josh Paetzel wrote:
> On Tue, Mar 26, 2002 at 09:21:57PM -0800, Terry Lambert wrote:
> > Alfred Perlstein wrote:
> > > > But if system calls aren't preempted under what circumstances can a
> > > > process hold a vnode lock and then be usurped for processor?
> > >
> > > While sleeping for IO.
> >
> > Ideal systems release and reacquire locks when they are going
> > to suspend for a long time (Djikstra's "Banker's Algorithm").
> 
> Of course, the downside of this is that a low priority process that
> needs a lot of resources may never be able get all of the resources
> that it needs.  :)

That's a feature, not a bug.

-- Terry

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