> In article <199806301811.UAA28870@horn.ics.muni.cz>,
> Zdenek Salvet  <salvet@ics.muni.cz> wrote:
> > > However, this one, I'm not so sure about:
> > > #define	S_IFNONRES	0400000		/* file is non-resident */
> > 
> > I would let the HSM VFS module to manage this information internally
> > (e.g. in one database file). It is no use for normal filesystems
> > and for special things like HSM you will always need additional special
> > attributes that would unnecessarily pollute the interface and you would run
> 
> The VFS doesn't care about those other attributes, so they can and
> should stay in the HSM database.  The VFS should be very thin, and only
> care wether the file is in layer one or not.  A file flag can be tested
> much more cheaply than a query to the HSM database. 

If cached reasonably, queries to the HSM database need not be slower
than normal (cached) inode reads from disk.

-- 
Zdenek Salvet                                              salvet@ics.muni.cz 
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