Re: Re: Perfomance problem backupscript (more details and tests)

On Thu, Oct 06, 2005 at 01:14:04PM +0200, [email protected] wrote:

> The ctime-quirk seems to be dependend on the type of
> filesystem and on the version of Linux. It has been
> patched into the code without revising documentation.
> It might get patched out of the code as well.
> http://sourceforge.net/mailarchive/forum.php?thread_id=3726620&forum_id=6379 :
> "Unfortunately, however, the change was not pushed
>  into 2.3, and so 2.4 and now 2.6 have a ext2 rename()
>  implementation that does not update inode ctime."

Given that ctime's purpose was to allow correct incremental backups, not
adjusting it in rename is broken.  The joys of Linux are that only popular
bugs tend to be fixed.  Since most people don't do backups, these kinds of
things don't tend to be very popular.  (Of those that do backups, most
don't try restoring them, so they only find out after a disaster that
things aren't right).

Unfortunately, the Posix standard itself waffles on this issue and sys that
some systems update the c_time and some do not.  I guess Linux complies
with this by sometimes updating the c_time :-(.

Dave