Re: Swap

[Steffen Persvold]

Christopher Friesen wrote:
> 
> "Richard B. Johnson" wrote:
> >
> > On Tue, 20 Nov 2001, Wolfgang Rohdewald wrote:
> >
> > > On Tuesday 20 November 2001 15:51, J.A. Magallon wrote:
> > > > When a page is deleted for one executable (because we can re-read it from
> > > > on-disk binary), it is discarded, not paged out.
> > >
> > > What happens if the on-disk binary has changed since loading the program?
> > > -
> >
> > It can't. That's the reason for `install` and other methods of changing
> > execututable files (mv exe-file exe-file.old ; cp newfile exe-file).
> > The currently open, and possibly mapped file can be re-named, but it
> > can't be overwritten.
> 
> Actually, with NFS (and probably others) it can.  Suppose I change the file on
> the server, and it's swapped out on a client that has it mounted.  When it swaps
> back in, it can get the new information.
> 

This sounds really dangerous... What about shared libraries ??

Regards,
-- 
  Steffen Persvold   | Scalable Linux Systems |   Try out the world's best   
 mailto:[e-mail]  |  http://www.scali.com  | performing MPI implementation:
Tel: [phone] |   Olaf Helsets vei 6   |      - ScaMPI 1.12.2 -         
Fax: [phone] |   N0621 Oslo, NORWAY   | >300MBytes/s and <4uS latency