On Fri, Sep 05, 2014 at 11:24:04AM +1000, Dave Chinner wrote: > On Thu, Sep 04, 2014 at 08:04:51PM -0500, Eric Sandeen wrote: > > On 9/4/14, 7:45 PM, Dave Chinner wrote: > > >On Thu, Sep 04, 2014 at 12:38:28PM -0400, Brian Foster wrote: > > >>xfsdump encodes and stores the full atime and mtime for each file with > > >>nanosecond resolution. xfsrestore uses utime() to set the times of each > > >>file that is restored. The latter supports resolution of 1 second, thus > > >>sub-second timestamp data is lost on restore. > > > > > >That doesn't seem like a big deal. What sort of problems does this > > >actually cause? > > > > > >FYI, many linux filesystems only have second resolution timestamps > > >and hence applications can't rely on sub-second timestamp resolution > > >to actually mean anything useful.... > > > > But why not restore the same resolution as is actually stored in the dump? > > Throwing it away seems odd, and restoring it looks easy enough. > > Comes from a time when we couldn't restore what was in the dump. :/ > > > In any case, there was a user who noticed & complained. Seems like a > > very reasonable thing to fix, to me. > > Sure, but we don't make changes with the justification "just > because". xfsrestore has had this behaviour since dump/restore was > first introduced, so first we need to understand what the actual > problem is. Was the user complaining because they noticed they were > "different" in passing, or was it noticed because the difference is > the root cause of some other problem? > No problems that I'm aware of. As Eric mentioned, it was noticed during an evaluation of possible data transfer mechanisms for a glusterfs setup. The user had to evaluate whether it would lead to any issues (a geo-replication tracking thing I suspect) for a customer, but I hadn't heard anything that suggested it was. The utime() call appears to be obsolete as well, for whatever that's worth. Brian > Cheers, > > Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
