dsync not updating times correctly

Hello,

I recently discovered mpifileutils and they are awesome. I moved about 200 TB in 4 million files between two different lustre filesystems over the weekend. Thank you for your work on these tools. After doing an initial data move, my intent was to keep the data in sync for a period of time using rsync. With the bulk of the data transferred, this should go fast but it would also catch any file types that `dsync doesn't handle (hard links, etc.). Here is the script I'm using.

source=/nobackup/PROJECTS/ccdev/
dest=/nobackup2/PROJECTS/ccdev/

mpiexec --allow-run-as-root dsync -X non-lustre $source $dest > dsync-ccdev.out.$( date +%F )

rsync -aPHASx $source $dest > rsync-ccdev.out.$( date +%F )

The problem I'm running into is that rsync is copying files that dync already copied. Here is one example of a file that rsync is trying to transfer again.

Source:

238412051 -rw-r----- 1 dvicker eg3 244210724864 Aug 23 16:38 /nobackup/PROJECTS/ccdev/boeing/aero/adb/ar/ar-204.squashfs

Destination:

238487228 -rw-r----- 1 dvicker eg3 244210724864 Sep 29 17:15 /nobackup2/PROJECTS/ccdev/boeing/aero/adb/ar/ar-204.squashfs

The file size it correct but it looks like the date on the destination is wrong - this is the date that that the file got created. After poking around in the destination more, it looks like this is prevalent - dates were not preserved. This will trip up rsync's default algorithm of checking by date and size. I could switch to rsync's checksum mode to get around this but that will be quite a bit more time consuming for this dataset.

Is this a bug with dsync or am I possibly doing something wrong? I'm using version 0.11.1 of mpifileutils.

Start with the dsync entry point and reproduce the provided mpiexec command on a smaller source and destination pair. Compare source and destination modification times after dsync, then verify that rsync no longer recopies equal-size files. Done means dsync preserves the timestamps for supported filesystems, with a regression test if the project has coverage for this behavior.