ctime vs mtime

So about that huge file cleanup . . .  it seems that Netapp's ndmpcopy resets all the files' ctimes.  (Meaning there were changes to the inodes somewhere in the process).  Fortunately, the mtimes were preserved so I was able to generate a proper distribution-over-time stat.

I can only assume (since the guy who ran the ndmpcopy swears he didn't do anything else), that that means ndmpcopy is actually creating the inodes on the fly rather copying the existing ones over.  Good to know.  (rsync preserves those stamps the way I usually run it, so I've never run into this issue before.)