[Gluster-devel] AFR conservative merge portability

[Ravishankar N]

On 12/18/2014 01:28 PM, Emmanuel Dreyfus wrote:
> On Mon, Dec 15, 2014 at 03:21:24PM -0500, Jeff Darcy wrote:
>> Is there *any* case, not even necessarily involving conservative merge,
>> where it would be harmful to propagate the latest ctime/mtime for any
>> replica of a directory?
> 
> In case of conservative merge, the problem vanish on its own anyway:
> adding entries updates parent directory ctime/mtime and the reported
> split brain does not exists anymore.
> 
> Here is a first attempt, please comment:
> http://review.gluster.org/9291
> 

Hi Emmanuel,
So we (AFR team) had a discussion and came up with two things that need to be done w.r.t. this issue:

1. First in metadata heal, if the metadata SB is only due to [am]time, heal the file choosing the source as the one having the max of atime/mtime.

2. Currently in entry-self heal, after conservative merge, the dir's timestamp is updated using the time when self heal happened and not that of the dirs on the bricks.
   This needs to be changed to use the timestamp of the source having max mtime, similar to what data selfheal does in afr_selfheal_data_restore_time()

Point #1 would be addressed by your patch with some modifications (pending review );that just leaves #2 to be done.

Thanks,
Ravi