[saturnero@freesbie.org: Weird behaviour of mount_unionfs with executables]

[Stephan Uphoff]

On Sun, 2005-07-03 at 20:02, Scott Long wrote:
> Stephan Uphoff wrote:
> > I suspect the changes in revision 1.272 of kern_exec.c trigger the
> > copy operation.
> > 
> > Looks like you need a noatime option for union_fs.
> > 
> > Stephan
> 
> Does this mean that every vnode that gets executed gets dirtied and all
> its pages resynced to the backing store, or just the inode block?

The kernel calls VOP_SETATTR to set the access time of the file.
union_fs detects that it does not have an upper layer copy of the file
to modify the attributes on and decides to copy it.
The vm layer does not (directly) come into play on this. 

Stephan