Re: rfc: [patch] change attribute for ext3

["Randy.Dunlap" <rdunlap@xenotime.net>]

On Wed, 13 Sep 2006 15:06:02 -0400 Trond Myklebust wrote:

> On Wed, 2006-09-13 at 20:30 +0200, Alexandre Ratchov wrote:
> > On Wed, Sep 13, 2006 at 02:11:11PM -0400, Trond Myklebust wrote:
> > > On Wed, 2006-09-13 at 18:42 +0200, Alexandre Ratchov wrote:
> > > > hello, 
> > > > 
> > > > here is a small patch that adds the "change attribute" for ext3
> > > > file-systems;
> > > > 
> > > > the change attribute is a simple counter that is reset to zero on
> > > > inode creation and that is incremented every time the inode data is
> > > > modified (similarly to the "ctime" time-stamp).
> > > 
> > > I would really have preferred a full-blown 64-bit counter as per
> > > RFC3530, but I suppose we could always combine this change attribute
> > > with the high word from ctime in order to make up the NFSv4 change
> > > attribute. That should keep us safe until someone develops a ramdisk
> > > with < 1 nsecond access time.
> > > 
> > 
> > do you mean something like "(ctime.tv_sec << 32) | change_attribute"? this
> > would allow 2^32 inode changes per second.
> 
> Yes. As I said, that probably ought to suffice for now.
> 
> > For ext3 it's hard to find unused bits in the on-disk inode structure, but
> > ext4 inode may become larger in the future, allowing a 64bit counter.
> 
> In anticipation of that event, could you please change the field in
> 'struct stat' and 'struct stat64' to be an 'unsigned long long' instead
> of the current 'unsigned long'?
> 
> All the other fields are internal to the kernel, so a future change of
> their size should not matter.

and while you are making changes + resubmitting,
Signed-off-by:
needs to have name + email address.

---
~Randy