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Re: Reclaiming vnodes

On Wed, Sep 23, 2009 at 08:50:59PM +0300, Antti Kantee wrote:
> On Wed Sep 23 2009 at 09:40:26 -0700, Bill Stouder-Studenmund wrote:
> > > But vnodes doesn't need to be reclaimed so often as allocated. I think  
> > > that allocation is more critical then  speed of reclaim.
> > 
> > Huh? After we reach the max # of vnodes, every allocated vnode comes from 
> > a vnode being cleaned.
> > 
> > Also, since you have one thread, what happens when one file system is slow 
> > about reclaiming a vnode? Say an nfs mount that's having problems. Or a 
> > disk array that is having a lot of i/o errors that take a while but which 
> > it's recovering from. Your one thread now stalls, and so you can starve 
> > the whole OS of vnodes.
> With the patch vnodes are vnalloc()'d always.  So you're not starving
> the OS of vnodes ...

Oh. That's bad. We really do need to be able to bound the # of vnodes.

> I think it's becoming very clear that the proposed change is not
> acceptable in the grand scheme of things and debating details will not
> change this.

Ok. I'll hush for now (or until the thread awakens with gusto :-) )

Take care,


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